U.S. flag

An official website of the United States government

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2022.

Cover of GeneReviews®

GeneReviews® [Internet].

Show details

Monosomy 7 Predisposition Syndromes Overview

, MD, PhD, , MD, , MD, and , MD, PhD.

Author Information

Initial Posting: .

Estimated reading time: 33 minutes

Summary

The purpose of this overview is to increase the awareness of clinicians regarding germline pathogenic variants that predispose to the development of monosomy 7 and discuss medical management of monosomy 7 predisposition syndromes and risk assessment of at-risk asymptomatic relatives.

The following are the goals of this overview.

Goal 1.

Describe the clinical characteristics of monosomy 7 predisposition syndromes.

Goal 2.

Review the genetic causes of monosomy 7 predisposition.

Goal 3.

Provide an evaluation strategy to identify the genetic cause of monosomy 7 predisposition in a proband (when possible).

Goal 4.

Review the differential diagnosis of monosomy 7 predisposition syndromes.

Goal 5.

Inform (when possible) medical management of monosomy 7 predisposition syndromes.

Goal 6.

Provide a basic view of genetic risk assessment of at-risk asymptomatic relatives of a proband with a monosomy 7 predisposition syndrome to inform surveillance and to allow early diagnosis so that definitive therapy with bone marrow transplantation can be initiated prior to the emergence of a leukemic clone.

1. Clinical Characteristics of Monosomy 7 Predisposition Syndromes

Clinical Description

Monosomy 7 predisposition syndromes are typically characterized by childhood or young-adult onset of bone marrow insufficiency associated with an increased risk for severe cytopenias, variable adaptive immune deficiency, bone marrow aplasia, myelodysplastic syndrome (MDS), and/or acute myeloid leukemia (AML) [Babushok et al 2016]. Monosomy 7 is identified in peripheral blood and/or bone marrow cells and represents a clonal acquired cytogenetic alteration. To date, constitutional monosomy 7 has not been identified.

Systemic anomalies associated with monosomy 7 predisposition syndromes can include multiple organ system involvement and delays in growth and neurodevelopment (see Table 1).

Disorders that predispose to monosomy 7 were included in the 2016 revision of the World Health Organization (WHO) classification of myeloid neoplasms and AML, in a new category: "myeloid neoplasms with germline predisposition" [Arber et al 2016]; recognition of these disorders was also supported by the updated 2017 European LeukmiaNET (ELN) recommendations, with a new category of the same name [Döhner et al 2017].

Childhood to young adult onset. In large multicenter cohorts of children and young adults, monosomy 7 is found in approximately 20% of individuals with MDS and 5% of individuals with AML [Wlodarski et al 2018]. Notably, however, the frequency of monosomy 7 has been reported as high as 41% of single center cohorts of children with primary MDS [Schwartz et al 2017a]. A germline genetic predisposition to monosomy 7 can be identified in the majority of these individuals. Older adults with MDS and/or AML are less likely to have monosomy 7 and older individuals with monosomy 7 are less likely to have an identifiable genetic predisposition associated with the development of monosomy 7 [Schratz & DeZern 2020].

Bone marrow insufficiency. Most affected individuals present with clinical evidence of bone marrow insufficiency such as petechiae, easy bruising, fatigue, pallor, or opportunistic infections. Children presenting with refractory cytopenias often demonstrate thrombocytopenia and neutropenia, as opposed to the common presentation of isolated refractory anemia observed in adults [Kardos et al 2003]. Additional laboratory features include red cell macrocytosis and increased hemoglobin F concentration. Some individuals may have single-lineage isolated cytopenias, whereas others meet blood count criteria for severe aplastic anemia (granulocyte count <500/μL, platelet count <20,000/μL, absolute reticulocyte count <60,000/μL). In most individuals, bone marrow examination reveals hypocellularity, aplasia, or morphologic features consistent with refractory cytopenia of childhood (RCC) [Niemeyer & Baumann 2011]. RCC remains a provisional entity in the 2016 revision of the WHO classification grouping pediatric MDS without excess blasts into one category regardless of the degree of dysplasia or cellularity. In some individuals, however, the marrow will have normal or increased cellularity and evidence of excess blasts.

Note: Individuals meet WHO 2016 criteria for MDS [Arber et al 2016] if they have cytopenias, evidence of single or multilineage dysplasia, and up to 19% peripheral or bone marrow blasts. Individuals meet WHO 2016 criteria for AML with MDS-related changes if they have bone marrow dysplasia and 20% or greater blood or bone marrow blasts.

G-banded cytogenetic analysis or deletion/duplication analysis (e.g., microarray, FISH, quantitative PCR) of peripheral blood or bone marrow cells demonstrates a 45,XX,-7 karyotype in females and 45,XY,-7 karyotype in males, typically mosaic with normal cells (i.e., 46,XX in females and 46,XY in males). While complete loss of chromosome 7 is most common, partial deletion of 7q (del7q), the unbalanced der(1;7)(q10;p10) translocation, and additional unbalanced translocations that also result in monosomy 7q are considered within the spectrum of monosomy 7 disorders [Inaba et al 2018]. Testing should be performed on unstimulated samples if possible (i.e., without PHA or other mitogens) because stimulation can mask cells with monosomy 7. A minimum of three in 20 cells lacking a chromosome 7 confirms the diagnosis of monosomy 7. Additionally, a high percentage of monosomy 7 marrow cells by G-banded cytogenetic analysis of unstimulated cells can be attributable to either replacement of normal bone marrow cells by abnormal cells or high endogenous mitotic activity of the abnormal cells. A minimum of 20 unstimulated metaphase cells should be analyzed for a complete cytogenetic analysis.

Note: (1) Individuals with monosomy 7 predisposition syndromes may initially have a normal karyotype in peripheral blood and/or bone marrow and over time transition to develop clonal monosomy 7 in peripheral blood and/or bone marrow. Thus, normal cytogenetic studies in either peripheral blood or bone marrow at the onset of hematologic disease do not eliminate the possibility of subsequent loss of a chromosome 7 associated with bone marrow failure, MDS, and/or AML. (2) In some individuals, treatment with steroids, which inhibit the growth of cells in culture, can mask the cytogenetic identification of monosomy 7. However, monosomy 7 would be identifiable by fluorescence in situ hybridization (FISH) or microarray analysis; therefore, FISH or microarray is preferred when performing longitudinal assessment of clonal percentage.

Family history. Monosomy 7 predisposition syndromes may occur de novo in the proband or be inherited. Affected family members can be asymptomatic and have normal laboratory evaluation; laboratory findings in affected family members may also be subtle and include macrocytic red blood cells (MCV >94 fL), increased hemoglobin F concentration, and mild cytopenias.

Rapid progression is common once monosomy 7 has developed. Many individuals progress to advanced MDS or AML within months of monosomy 7 detection, though instances of more indolent progression have been reported [Rentas et al 2020]. Monosomy 7 may directly contribute to leukemogenesis due to the resultant haploinsufficiency of EZH2 which encodes a histone methyltransferase that constitutes the catalytic component of PRC2. PRC2 functions as a tumor suppressor in myeloid progenitor cells. Deficient PRC2 activity primes the hematopoietic landscape for leukemic transformation and confers a poor prognosis despite treatment intensification in pediatric AML [Bond et al 2018]. EZH2 deficiency specifically confers treatment resistance [Göllner et al 2017]. At least one preclinical model has questioned the specificity of EZH2 deficiency leading to myeloid versus lymphoid leukemias [Simon et al 2012] and thus these pathways continue to require further explanation [Inaba et al 2018].

In individuals with monosomy 7 and progressive features of MDS or AML, prognosis is poor without aggressive chemotherapy and hematopoietic stem cell transplantation [Locatelli & Strahm 2018]. Even with treatment, nearly half of individuals die of MDS/AML or treatment complications if monosomy 7 is the main cytogenetic abnormality [Hasle and Niemeyer 2011]. Mortality is even higher for those with monosomy 7 as part of a complex karyotype [Göhring et al 2010].

Some individuals diagnosed in early childhood with a monosomy 7 predisposition syndrome in the absence of advanced MDS or AML may exhibit regression and resolution of the monosomy 7 clone(s) [Parker et al 2008, Csillag et al 2019]. At least eight individuals, ranging in age at diagnosis from eight months to three years, have been reported with transient monosomy 7 that regressed with age. Germline pathogenic variants in SAMD9L and SAMD9 have been identified in individuals with transient monosomy 7 [Pastor et al 2018]. In these individuals, the monosomy 7 clones either resolved with no other clonal hematopoiesis detected or were replaced by clones with uniparental disomy of 7q, resulting in a diploid copy of the normal SAMD9 or SAMD9L allele located on 7q [Schwartz et al 2017b, Wong et al 2018, Csillag et al 2019]. To date, development of transient monosomy 7 and subsequent resolution has not been described in other monosomy predisposition syndromes.

2. Causes of Monosomy 7 Predisposition Syndromes

Table 1.

Monosomy 7 Predisposition Syndromes: Genes and Clinical Features

Gene(s) 1Disorder (See footnotes for monosomy 7 predisposition references.)MOI% of All Monosomy 7 PredispositionTypical Onset of Monosomy 7Distinguishing Clinical Features
BLM (RECQL3)Bloom syndrome 2AR1%-5%ChildhoodSevere pre- & postnatal growth deficiency, immune abnormalities, sensitivity to sunlight, insulin resistance, high risk for early-onset cancers
BRCA2
BRIP1
FANCA
FANCB
FANCC
FANCD2
FANCE
FANCF
FANCG
FANCI
(>20
genes) 3
Fanconi anemia 4AR
XL 3
5%-15%Childhood to adultCongenital anomalies, bone marrow failure, ↑ risk for malignancy
NF1 Neurofibromatosis 1 5AD5%-10%Early childhoodCafé au lait macules, axillary & inguinal freckling, cutaneous neurofibromas, Lisch nodules
CBL
KRAS
NRAS
PTPN11
Rasopathies (See Noonan syndrome.) 5, 6ADEarly childhoodCharacteristic facial features, short stature, congenital heart disease, variable DD
CEBPA CEBPA-associated familial AML 7AD1%-5%Childhood to adultNo addl features aside from highly penetrant AML
DDX41 DDX41-associated familial myelodysplastic syndrome and acute myeloid leukemia 8AD1%-5%AdultNo addl features aside from MDS/AML
DNAJC21
ELF1
SBDS
SRP54
Shwachman-Diamond syndrome 9AD
AR
1%-5%Childhood to adultExocrine pancreatic dysfunction w/malabsorption, malnutrition, & growth failure; hematologic abnormalities w/single- or multilineage cytopenias & susceptibility to MDS & AML; bone abnormalities incl metaphyseal dysplasia
ELANE
G6PC3
GFI1
HAX1
JAGN
TCRG1
VPS45A
Severe congenital neutropenia 10
(See ELANE-Related Neutropenia.)
AD
AR
1%-5%Childhood to adultSevere neutropenia, recurrent infections
ERCC6L2 Bone marrow failure syndrome 2 (OMIM 61571511AR1%-5%AdultMicrocephaly, learning difficulties, DD
GATA1 12GATA1-related Diamond-Blackfan anemia 13XL<1%Unknown 14Pure red cell aplasia
GATA2 GATA2 deficiency 15 (OMIM 137295)AD35%-40%Childhood to adultMonoMAC syndrome (monocytopenia, nontuberculous mycobacterial infections), Emberger syndrome (lymphedema & monosomy 7), cutaneous warts, congenital deafness, neutropenia, alveolar proteinosis, DCML
LIG4 Ligase 4 syndrome 16 (OMIM 606593)AR<1%Unknown 14Microcephaly, growth failure, DD, skeletal malformations, bone marrow failure, immunodeficiency, lymphoma
MLH1
MSH2
MSH6
PMS2
Constitutional mismatch repair deficiency 17 (See Lynch Syndrome.)AR<1%ChildhoodHigh risk for many cancers
RUNX1 RUNX1 familial platelet disorder w/associated myeloid malignancies 18AD<1%AdultThrombocytopenia, bleeding tendency
SAMD9 MIRAGE syndrome 19AD10%-20%ChildhoodRecurrent infections, restricted growth, adrenal hyperplasia, genital abnormalities, enteropathy, renal abnormalities
SAMD9L SAMD9L ataxia-pancytopenia syndrome 19ADChildhoodAtaxia, pancytopenia, neutrophilic dermatosis
TP53 Li-Fraumeni syndrome 20AD2%-5%Childhood to adultHigh risk for many cancers & therapy-related AML
WRN Werner syndrome 21AR<1%Unknown 14Accelerated aging, cataracts, diabetes mellitus, osteoporosis
XPC Xeroderma pigmentosum group C 22AR<1%AdultSensitivity to UV radiation, ↑ risk of skin cancer

AD = autosomal dominant; AML = acute myeloid leukemia; AR = autosomal recessive; DCML = dendritic cell, monocyte, and B and natural killer cell lymphoid deficiency; DD = developmental delay; MDS = myelodysplastic syndrome; MOI = mode of inheritance; XL = X-linked

1.

Genes are listed alphabetically

2.
3.

Listed genes represent the most common genetic causes of Fanconi anemia (FA). For other genes associated with this phenotype (>20 genes have been identified), see Fanconi Anemia. FA can be inherited in an autosomal recessive manner, an autosomal dominant manner (RAD51-related FA), or an X-linked manner (FANCB-related FA).

4.
5.
6.

Although additional genes have been associated with Noonan syndrome, only those listed here have been definitively linked to monosomy 7.

7.
8.
9.
10.
11.
12.

Although 20 genes in addition to GATA1 have been associated with Diamond-Blackfan anemia; only GATA1-related Diamond-Blackfan anemia has been definitively linked to monosomy 7.

13.
14.

Too few cases described to determine age of onset

15.
16.
17.
18.
19.
20.
21.
22.

3. Evaluation Strategies to Identify the Genetic Cause of Monosomy 7 Predisposition in a Proband

Establishing a specific genetic cause for predisposition to monosomy 7:

  • Can aid in discussions of prognosis (which are beyond the scope of this GeneReview) and genetic counseling;
  • Usually involves a medical history, physical examination, laboratory testing, family history, and genomic/genetic testing.

Medical history. A detailed medical history is critical to distinguish disorders that predispose to monosomy 7 (Table 1) and to assess for comorbid medical conditions:

  • Hematologic. Results from CBC and bone marrow examinations including cytopenias, marrow cellularity, and red cell macrocytosis; symptoms of cytopenias including easy bruising, prolonged bleeding, fatigue, pallor, and frequent bacterial infections
  • Immune/infection. Prior immunologic testing, autoimmune/rheumatologic symptoms, lymphedema, atypical infections (e.g., viral, mycobacterial, fungal)
  • Birth history / congenital anomalies. Intrauterine growth restriction, low birth weight, prematurity; congenital heart, genitourinary, renal, vertebral, radioulnar, and digit anomalies; tracheoesophageal fistula
  • Dermatologic conditions. History of birthmarks, rashes, or skin lesions requiring prior dermatologic care/removal
  • Malignancies. Location, pathologic/molecular classification, and therapies received
  • Other. Endocrine disorders (adrenal insufficiency, short stature); gastrointestinal abnormalities (steatorrhea, other symptoms of pancreatic insufficiency); failure to thrive; symptoms of hepatic dysfunction; chronic pulmonary disease; neurologic/developmental abnormalities
  • Environmental exposures. Personal/family occupation history; travel history; medication, supplement, and recreational drug use

Physical examination. Findings on physical examination may suggest a specific monosomy 7 predisposition disorder:

  • Short stature is seen in many conditions including Shwachman-Diamond syndrome, Fanconi anemia, and MIRAGE syndrome
  • Microcephaly is seen in Fanconi anemia, ligase 4 syndrome, and ERCC6L2-related bone marrow failure syndrome
  • Café au lait macules may be seen in Fanconi anemia and neurofibromatosis I. Axillary freckling and cutaneous neurofibromas are specific to neurofibromatosis 1.
  • Cardiac murmurs may be identified in Fanconi anemia and rasopathies due to underlying congenital heart disease.
  • Lymphedema and pulmonary auscultation abnormalities may be features of GATA2 deficiency.
  • Cerebellar ataxia is seen in SAMD9L ataxia-pancytopenia syndrome.
  • Bruising and petechiae may be associated with any monosomy 7 predisposition syndrome after onset of severe cytopenias; however prolonged bleeding in the absence of severe thrombocytopenia or advanced MDS or AML may be suggestive of RUNX1 familial platelet disorder with associated myeloid malignancies.
  • Hepatosplenomegaly is infrequently present in early-stage MDS, but is associated with advanced myeloid malignancy; however, rasopathies associated with monosomy 7 and myeloproliferative diseases are most commonly associated with hepatosplenomegaly.
  • Skeletal dysplasia may be a feature of Shwachman-Diamond syndrome.

Family history. A three-generation family history should be taken, with attention to relatives with manifestations of monosomy 7 predisposition syndromes and documentation of relevant findings through direct examination or review of medical records, including results of molecular genetic testing. Specific family history features of monosomy 7 predisposition syndromes include the following:

  • Early-childhood deaths and/or maternal history of miscarriages
  • Early-onset or atypical cancer diagnoses. Excessive toxicity associated with cancer treatment
  • Syndromic features/congenital anomalies
  • Consanguinity
  • Neonatal transient cytopenias
  • Bone marrow failure or immune deficiencies
  • Lymphedema
  • History of atypical and/or prolonged bleeding
  • Severe developmental delay and other neurologic abnormalities

Laboratory testing

Molecular genetic testing approaches can include a combination of gene-targeted testing (multigene panel or serial single-gene testing) and comprehensive genomic testing (exome sequencing, genome sequencing). Gene-targeted testing requires the clinician to hypothesize which gene(s) are likely involved, whereas genomic testing does not.

Note: Skin (considered gold standard) or buccal fibroblasts are the preferred tissue type for germline molecular testing for individuals suspected to have a monosomy 7 predisposition syndrome due to somatic revertant mutation or functional deletion of germline pathogenic variants through chromosome loss or loss of heterozygosity that can occur in bone marrow and blood cells from individuals with monosomy 7. In situations where rapid therapy decision making is required, molecular genetic testing may be initially performed on blood or bone marrow samples, and subsequently performed on cultured skin fibroblasts which may take longer to obtain results.

  • Serial single-gene testing can be considered if clinical findings and/or family history indicate that pathogenic variants in a particular gene are most likely (see Table 1).
  • A multigene panel that includes some or all of the genes listed in Table 1 is most likely to identify the genetic cause of the condition while limiting identification of variants of uncertain significance and pathogenic variants in genes that do not explain the underlying phenotype. Note: (1) The genes included in the panel and the diagnostic sensitivity of the testing used for each gene vary by laboratory and are likely to change over time. (2) Some multigene panels may include genes not associated with the condition discussed in this GeneReview. (3) In some laboratories, panel options may include a custom laboratory-designed panel and/or custom phenotype-focused exome analysis that includes genes specified by the clinician. (4) Methods used in a panel may include sequence analysis, deletion/duplication analysis, and/or other non-sequencing-based tests.
    Note: Identification of a variant(s) of uncertain significance in one of the genes listed in Table 1 does not establish or rule out the diagnosis.
    For an introduction to multigene panels click here. More detailed information for clinicians ordering genetic tests can be found here.
  • Comprehensive genomic testing (which does not require the clinician to determine which gene[s] are likely involved) may be considered. Exome sequencing is most commonly used; genome sequencing is also possible.
    For an introduction to comprehensive genomic testing click here. More detailed information for clinicians ordering genomic testing can be found here.

4. Differential Diagnosis of Monosomy 7 Predisposition Syndromes

The differential diagnosis of monosomy 7 predisposition syndromes includes:

Sporadic Monosomy 7 MDS/AML

Sporadic monosomy 7 MDS/AML refers to monosomy 7 MDS/AML that arises without evidence of germline genetic predisposition and in the absence of other predisposing medical conditions or treatments. Monosomy 7 MDS/AML that occurs in older adults is typically considered to be sporadic (i.e., the result of a chance occurrence of a disorder or abnormality that is not expected to recur in a family) and is associated with clonal hematopoiesis of indeterminate potential, a common age-related phenomenon [Babushok et al 2016]. In childhood- or young adult-onset monosomy 7, while most individuals are found to have either a known monosomy 7 predisposition syndrome preceding bone marrow failure, or prior cancer therapy, there are many individuals in whom a predisposing condition cannot be identified. It is currently unknown if some individuals with childhood or young-adult onset represent sporadic acquisition of monosomy 7 or if monosomy 7 has arisen as the result of an unidentified germline molecular cause. Individuals with no prior personal or family history of malignancies, bone marrow failure, or immune deficiency are more likely to have sporadic monosomy 7, whereas those with a family history of monosomy 7 (i.e., multiple affected family members) should be suspected of having a monosomy 7 predisposition syndrome even in the absence of an identified pathogenic variant in a known predisposition gene.

Secondary Monosomy 7 Arising from Acquired Bone Marrow Failure

Monosomy 7 is the most common somatic cytogenetic abnormality identified in persons with secondary MDS/AML who were previously diagnosed with an acquired bone marrow failure disorder (e.g., acquired aplastic anemia and paroxysmal nocturnal hemoglobinuria) [Dumitriu et al 2015]. In a large North American series of individuals with pediatric aplastic anemia treated with immune suppression therapy, monosomy 7 occurred in 3.5% of individuals [Rogers et al 2019]. In adult-onset acquired aplastic anemia, the percentage of individuals that develop monosomy 7 may be as high as 5%-10% [Stanley et al 2017]. Monosomy 7 also occurs frequently in individuals who initially develop clonal paroxysmal nocturnal hemoglobinuria (PNH) as the predominant acquired bone marrow failure manifestation but later transition to MDS/AML [Araten et al 2001, Sun & Babushok 2020]. Notably in these individuals, the clone with monosomy 7 is thought to replace the PNH clone rather than occur as an additional hit within the PNH clone itself.

Monosomy 7 Secondary to Prior Cancer Therapy

Monosomy 7 occurs in 27%-32% of therapy-related myeloid neoplasms [Kuzmanovic et al 2020, Schwartz et al 2021] and has long been associated with exposure to alkylating chemotherapy, including cyclophosphamide [Higgins & Shah 2020]. Recent evidence, however, suggests that as many as 20% of these myeloid neoplasms presumed to be therapy-related may actually be driven by germline monosomy 7 predisposition disorders that increased the risk for both the primary tumor and MDS [Takahashi 2019]. Therefore, persons with (presumed) therapy-related myeloid neoplasms associated with monosomy 7 should be investigated for monosomy 7 predisposition disorders.

Additionally, germline variants in genes encoding proteins involved in the glutathione S-transferase pathway and other drug metabolism pathways have been identified to alter susceptibility to therapy-related monosomy 7 [Churpek & Larson 2013], suggesting that the spectrum of germline predisposition to therapy-related myeloid diseases may be distinct from the spectrum of disorders associated with predisposition to monosomy 7 (as listed in Table 1).

Germline Genetic Disorders Associated with Myeloid Neoplasms Not Specifically Associated with Monosomy 7

Other germline predisposition disorders in which MDS and leukemia have been reported without a specific association with monosomy 7 are summarized in Table 2.

Table 2.

Disorders that Predispose to Myeloid Neoplasms without Monosomy 7

Gene(s)DisorderMOINonhematologic FindingsHematologic Findings
ACD
CTC1
DKC1
NHP2
NOP10
PARN
RTEL1
TERC
TERT
TINF2
WRAP53
Telomere biology disorders incl dyskeratosis congenitaAR
AD
XL
Immune deficiency, pulmonary fibrosis, hepatopulmonary syndrome, cancer predisposition incl leukoplakia, nail dystrophy, reticular rash, early grayingBone marrow failure; 30% develop MDS/AML; rarely, other types of lymphoma/leukemia
ANKRD26 ANKRD26-related thrombocytopenia ADNoneMild-to-moderate thrombocytopenia w/normal platelet size; erythrocytosis; ~10% develop MDS/AML.
ATM Ataxia-telangiectasia ARProgressive cerebellar ataxia, telangiectasias, immune deficiency, infections, high risk for solid tumorsLymphoma, T-cell leukemia; AML less common but occurs w/complex karyotype
ETV6 ETV6 thrombocytopenia & predisposition to leukemia ADPredisposition to solid tumors incl colorectal cancerThrombocytopenia, acute lymphoblastic leukemia (most common hematologic malignancy), MDS, AML, mixed-phenotype acute leukemia, lymphoma
MPL Congenital amegakaryocytic thrombocytopenia (OMIM 604498)AROrgan dysfunction due to hemorrhagic eventsTransfusion-dependent thrombocytopenia, progression to aplastic bone marrow failure; rarely, myeloid neoplasms
NBN Nijmegen breakage syndrome ARMicrocephaly, craniofacial features, growth deficiency, recurrent infections due to immune deficiency; DD, solid tumorsLymphoma, neutropenia; rarely, myeloid leukemia w/complex karyotypes
RPL5
RPL11
RPL35a
RPS10
RPS17
RPS19
RPS24
RPS26 1
Diamond-Blackfan anemia ADCraniofacial, upper limb, heart, & genitourinary malformations; poor growth; DDPure red cell aplasia, aplastic anemia, up to 20% develop MDS/AML.
SRP72 Bone marrow failure syndrome 1 (OMIM 614675)ADCongenital deafnessPancytopenia, myelodysplasia

AD = autosomal dominant; AML = acute myeloid leukemia; AR = autosomal recessive; DD = developmental delay; MDS = myelodysplastic syndrome; MOI = mode of inheritance; XL = X-linked

1.

Eleven additional ribosomal proteins have been associated with autosomal dominant Diamond Blackfan Anemia, though each at lower frequencies than the genes included in Table 2.

5. Management: To Inform (When Possible) Medical Management of Monosomy 7 Based on Genetic Cause

Evaluations Following Initial Diagnosis

Measures include urgent referral to a hematologist for evaluation of cytopenias and bone marrow abnormalities that appear prior to the development of acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) and urgent referral to a hematopoietic stem cell transplantation (HSCT) specialist to identify potential donors and determine a transplant strategy. Consultation with a clinical geneticist and/or genetic counselor is recommended.

Laboratory studies for hematologic status should include the following.

Peripheral blood studies

  • CBC, differential, reticulocyte count, and peripheral blood smear review monitored weekly to monthly based on stability
  • Serum lactate dehydrogenase, uric acid, BUN, and creatinine
  • Liver function studies including transaminases, alkaline phosphatase, total and conjugated bilirubin, total protein, albumin, and liver-dependent clotting factors
  • Immunologic evaluation including quantitative immunoglobulins and quantitative lymphocyte subsets
  • HLA typing of the affected individual, full sibs, and biological parents to identify suitable donors for HSCT (See Treatment of Manifestations for further evaluation of potential related donors.)

Bone marrow studies

  • Unilateral or bilateral bone marrow aspirate and biopsy
  • Morphologic assessments including bone marrow cellularity and assessment for dysplasia
  • Assessment for bone marrow blasts by flow cytometry or immunostains
  • Reticulin stain to assess for fibrosis
  • Iron stain to assess for ringed sideroblasts
  • Karyotype analysis on metaphase cells
  • FISH to assess for copy number changes or translocations involving chromosome 7 and changes in other chromosomes including 1, 3, 5, 8, 17, and 20
  • Molecular testing for somatic pathogenic variants in SETBP1, ASXL1, RUNX1, and RAS pathway genes associated with monosomy 7 (CBL, KRAS, NRAS, PTPN11)

Treatment of Manifestations

Individuals with a monosomy 7 predisposition syndrome who develop monosomy 7 clones require treatment by hematologists, oncologists, and HSCT specialists with expertise in the management of MDS and AML. In the majority of individuals with monosomy 7, the key to successful treatment is early diagnosis so that definitive therapy with HSCT can be initiated prior to the emergence of a leukemic clone. Once transformation into AML occurs, the probability that HSCT will fail to cure the disease increases significantly [Hasle & Niemeyer 2011].

Any child or young adult with monosomy 7 in combination with cytopenias and multilineage marrow dysplasia should, therefore, proceed to HSCT as soon as possible, unless rising blast count warrants cytoreductive chemotherapy prior to transplant. The optimal pre-transplant therapy for individuals with MDS and a monosomy 7 predisposition syndrome has yet to be defined [Nakano et al 2020]. Several monosomy 7 predisposition syndromes are associated with increased morbidity due to prolonged cytopenias following intensive chemotherapy prior to transplant, or due to preexisting immunodeficiency as seen in GATA2 haploinsufficiency. Thus for many syndromes, proceeding directly to HSCT without preceding cycles of cytoreductive chemotherapy is a standard approach [Peffault de Latour & Soulier 2016].

Since HSCT is the only effective treatment for the management of hematologic disease and the familial status of the disorder may not be known, rigorous evaluation of related donors is strongly suggested.

  • In individuals with a known germline pathogenic variant associated with monosomy 7 predisposition, potential related donors should have site-specific testing for the known variant.
  • In individuals without an identified germline pathogenic variant, the matched related donor should undergo CBC and consider bone marrow analysis for hematopoietic abnormalities. A matched related donor with a normal CBC and bone marrow analysis may not be an ideal candidate for individuals with monosomy 7 in whom a germline predisposition is unidentified; a fully matched unrelated donor may be more suitable.

AML. Prognosis is poor for those with AML and monosomy 7. Thus, children with monosomy 7 AML are often treated on high-risk AML protocols and offered HSCT with best available donor in first remission [Hasle et al 2007].

  • In individuals with bone marrow failure syndromes (e.g., Fanconi anemia) and monosomy 7 associated AML, transplant conditioning may need to be started during the aplastic phase after a chemotherapy cycle is administered, as these individuals may not exhibit appropriate count recovery following an AML induction chemotherapy cycle [Peffault de Latour & Soulier 2016].
  • Furthermore, individuals with monosomy 7 predisposition caused by Fanconi anemia and other inherited bone marrow failure syndromes (e.g., Shwachman Diamond syndrome) may exhibit excess toxicity to conventional chemotherapy and radiation doses used in myeloablation, and therefore may require reduction in conditioning intensity.
  • For individuals with other monosomy 7 predisposition syndromes, data remain too limited to determine whether standard protocols for myeloablation prior to HSCT should be modified.

Surveillance

In individuals with childhood-onset monosomy 7 detected in the absence of other clonal genetic abnormalities, multilineage dysplasia, or increased blasts in bone marrow or peripheral blood, close serial surveillance of bone marrow aspirates and biopsies that includes blast quantitation, karyotype, FISH, and molecular analysis for somatic pathogenic variants commonly acquired in MDS/AML may be considered as an alternative to HSCT. In some individuals, the monosomy 7 clone may show regression (e.g., SAMD9- and SAMD9L-related monosomy 7).

  • Initially, bone marrow examination may need to be performed every one to two months to assess for chromosome abnormalities and/or acquisition of somatic pathogenic variants in MDS-related genes, until monosomy 7 clone size stability and absence of further clonal progression has been established.
  • Thereafter, bone marrow examination may be decreased to twice yearly as long as the monosomy 7 clone persists. Worsening blood cytopenias, growth in monosomy 7 clone size, acquisition of additional chromosome abnormalities or somatic pathogenic variants in MDS-related genes, progression toward multilineage dysplasia, or excess blasts indicate need for curative HSCT.

If HSCT is not pursued due to the presence of severe medical comorbidities that would impair successful transplant outcome (e.g., severe pulmonary disease), annual bone marrow examination is recommended to provide prognostic information regarding anticipated timing of hematologic disease progression.

6. Risk Assessment and Surveillance of At-Risk Relatives for Early Detection and Treatment of Monosomy 7 Predisposition Syndromes

Genetic Risk Assessment

Monosomy 7 predisposition syndromes can be inherited in an autosomal dominant, autosomal recessive, or X-linked manner.

In individuals with a suspected monosomy 7 predisposition syndrome in whom no germline molecular diagnosis is found, the mode of inheritance that is most likely may be elucidated by taking a detailed, three-generation family history with attention to relatives with manifestations of monosomy 7 predisposition syndromes and documentation of relevant findings through direct examination or review of medical records, including results of molecular genetic testing.

The family history may suggest autosomal dominant inheritance (e.g., affected males and females in multiple generations), autosomal recessive inheritance (e.g., affected sibs and/or parental consanguinity), or X-linked inheritance (e.g., no male-to-male transmission) or the proband may appear to be the only affected family member (in which case he or she may have monosomy 7 predisposition syndrome as the result of a de novo pathogenic variant).

Note: If a proband has a specific syndrome associated with monosomy 7, counseling for that disorder is indicated (see Table 3).

Table 3.

Modes of Inheritance of Hereditary Disorders Known to be Associated with Monosomy 7 Predisposition Syndrome

MOIDisorderGenes
AD Neurofibromatosis 1 NF1
Rasopathies (See Noonan Syndrome.)CBL, KRAS, NRAS, PTPN11
CEBPA-associated familial AML CEBPA
DDX41-associated familial myelodysplastic syndrome and acute myeloid leukemia DDX41
GATA2 deficiency 1 GATA2
RUNX1 familial platelet disorder with associated myeloid malignancies 2 RUNX1
MIRAGE syndrome SAMD9
SAMD9L ataxia-pancytopenia syndrome SAMD9L
Li-Fraumeni syndrome TP53
AD or AR Shwachman-Diamond syndrome DNAJC21, ELF1, SBDS, SRP54
Severe congenital neutropenia (See ELANE-Related Neutropenia.)ELANE, G6PC3, GFI1, HAX1, JAGN, TCRG1, VPS45A
AR Bloom syndrome BLM
Bone marrow failure syndrome 2 3 ERCC6L2
Ligase 4 syndrome 4 LIG4
Constitutional mismatch repair deficiency (See Lynch Syndrome.)MLH1, MSH2, MSH6, PMS2
Werner syndrome WRN
Xeroderma pigmentosum group C XPC
AR, AD, or XL Fanconi anemia BRCA2, BRIP1, FANCA, FANCB, FANCC, FANCD2, FANCE, FANCF, FANCG, FANCI (>20 genes) 5
XLGATA1-related Diamond-Blackfan anemia GATA1

AD = autosomal dominant; AML = acute myeloid leukemia; AR = autosomal recessive; DD = developmental delay; MDS = myelodysplastic syndrome; MOI = mode of inheritance; XL = X-linked

1.
2.
3.
4.
5.

Listed genes represent the most common genetic causes of Fanconi anemia (FA). For other genes associated with this phenotype (>20 genes have been identified), see Fanconi Anemia. FA can be inherited in an autosomal recessive manner, an autosomal dominant manner (RAD51-related FA), or an X-linked manner (FANCB-related FA).

Autosomal Dominant Inheritance – Risk to Family Members in Families with a Known Predisposing Germline Pathogenic Variant

Parents of a proband

  • Some individuals with an autosomal dominant monosomy 7 predisposition syndrome may have inherited a predisposing germline pathogenic variant from a parent. A heterozygous parent may or may not have hematologic abnormalities and/or other related manifestations.
  • Alternatively, an individual diagnosed with a monosomy 7 predisposition syndrome may have a de novo pathogenic variant.
  • Molecular genetic testing is recommended for the parents of the proband (if feasible, use of DNA derived from nonhematopoietic tissue [e.g., skin fibroblasts, hair roots] may be considered, as germline pathogenic variants may not be detectable in leukocytes in some individuals). If the pathogenic variant found in the proband is not identified in either parent, the following possibilities should be considered:
    • The proband has a de novo pathogenic variant. Note: A pathogenic variant is reported as "de novo" if: (1) the pathogenic variant found in the proband is not detected in parental leukocyte DNA; and (2) parental identity testing has confirmed biological maternity and paternity; if parental identity testing is not performed, the variant is reported as "assumed de novo" [Richards et al 2015].
    • The proband inherited a pathogenic variant from a parent with germline mosaicism.
    • The proband inherited a pathogenic variant from a parent with somatically acquired loss of heterozygosity with preferential loss of the chromosome with the predisposing pathogenic variant. This somatic change (e.g., due to monosomy 7 or uniparental disomy 7) often occurs in hematopoietic tissue and results in a decreased fraction of cells with the variant, and may cause a false negative molecular result when testing leukocyte DNA.
  • Although rarely reported, the clinical family history of some individuals diagnosed with monosomy 7 predisposition syndromes may appear to be negative because of failure to recognize the disorder in family members, reduced penetrance, or phenotypic modification resulting from a natural protective second genetic event. Therefore, an apparently negative family history cannot be confirmed unless molecular genetic testing (optimally using DNA derived from nonhematopoietic tissue) has demonstrated that neither parent is heterozygous for the pathogenic variant identified in the proband.

Sibs of a proband. The risk to the sibs of the proband depends on the genetic status of the proband's parents:

  • If a parent of the proband has the predisposing pathogenic variant, the risk to the sibs of inheriting the pathogenic variant is 50%. The likelihood that a sib who inherits a pathogenic variant will have abnormal hematologic findings and/or other related manifestations depends on penetrance of the familial disorder and the possibility of phenotypic modification.
  • If the proband has a known predisposing pathogenic variant that cannot be detected in the leukocyte DNA of either parent, the recurrence risk to sibs is slightly greater than that of the general population because of the possibility of parental germline mosaicism and the possibility of a false negative result in a parent due to preferential loss of the chromosome with the pathogenic variant.
  • If the parents have not been tested for the pathogenic variant identified in the proband but are clinically unaffected, sibs are still presumed to be at increased risk for the monosomy 7 predisposition syndrome because of the possibility that a parent either: (1) has germline mosaicism; or (2) is heterozygous but does not have apparent manifestations of the disorder because of reduced penetrance or phenotypic modification resulting from a natural protective second genetic event.
  • The suitability of sibs who are potential bone marrow donors may be evaluated with molecular genetic testing (preferably using DNA from nonhematopoietic tissue) for the germline pathogenic variant identified in the proband (see Management, Treatment of Manifestations).

Offspring of a proband. Each child of an individual with an autosomal dominant monosomy 7 predisposition syndrome has a 50% chance of inheriting the causative germline pathogenic variant.

Other family members. The risk to other family members depends on the genetic status of the proband's parents: if a parent has the causative germline pathogenic variant, his or her family members may be at risk.

Autosomal Recessive Inheritance – Risk to Family Members in Families with Known Predisposing Germline Pathogenic Variants

Parents of a proband

  • The parents of a child with an autosomal recessive monosomy 7 predisposition syndrome are obligate heterozygotes (i.e., presumed to be carriers of one predisposing pathogenic variant based on family history).
  • Molecular genetic testing is recommended for the parents of a proband to confirm that both parents are heterozygous for a predisposing pathogenic variant and to allow reliable recurrence risk assessment. If a pathogenic variant is detected in only one parent, the following possibilities should be considered:
  • Individuals who are heterozygous for a pathogenic variant in a gene associated with autosomal recessive monosomy 7 predisposition have no known increased risk of developing monosomy 7-associated myeloid malignancies. However, individuals who are heterozygous for a pathogenic variant in a subset of these genes — including genes associated with Fanconi anemia and constitutional mismatch repair deficiency (see Lynch Syndrome) — are at increased risk for development of other forms of leukemia and nonhematologic cancer and require genetic counseling and routine screening for those conditions.

Sibs of a proband

  • If both parents are known to be heterozygous for a predisposing pathogenic variant, each sib of an affected individual has at conception a 25% chance of inheriting two causative pathogenic variants, a 50% chance of inheriting one pathogenic variant and being heterozygous, and a 25% chance of inheriting neither of the familial pathogenic variants.
  • Individuals who are heterozygous for a pathogenic variant in a gene associated with autosomal recessive monosomy 7 predisposition have no known increased risk of developing monosomy 7-associated myeloid malignancies. However, individuals who are heterozygous for a pathogenic variant in a subset of these genes — including genes associated with Fanconi anemia and constitutional mismatch repair deficiency (see Lynch Syndrome) — are at increased risk for development of other forms of leukemia and nonhematologic cancer and require genetic counseling and routine screening for those conditions.
  • The suitability of sibs who are potential bone marrow donors may be evaluated with molecular genetic testing for the germline pathogenic variants identified in the proband (see Management, Treatment of Manifestations).

Offspring of a proband. The offspring of an individual with an autosomal recessive monosomy 7 predisposition syndrome are obligate heterozygotes for a pathogenic variant.

Other family members. Each sib of the proband's parents is at a 50% risk of being heterozygous for a pathogenic variant.

Heterozygote Detection

Heterozygote testing for at-risk relatives requires prior identification of the pathogenic variants in the family.

X-Linked Inheritance – Risk to Family Members in Families with a Known Predisposing Germline Pathogenic Variant

Parents of a male proband

Sibs of a male proband. The risk to sibs depends on the genetic status of the mother:

Offspring of a male proband. Affected males transmit the predisposing pathogenic variant to: all of their daughters — who will be heterozygotes and will usually not be affected — and none of their sons.

Other family members. The maternal aunts and maternal cousins of a male proband may be at risk of having a predisposing pathogenic variant.

Note: Molecular genetic testing may be able to identify the family member in whom a de novo pathogenic variant arose, information that could help determine genetic risk status of the extended family.

Heterozygote Detection

Identification of female heterozygotes requires prior identification of the predisposing pathogenic variant in the family.

Surveillance

It is appropriate to evaluate apparently asymptomatic at-risk relatives of individuals with a history of a monosomy 7 predisposition syndrome as early as possible in order to allow initiation of HSCT prior to the emergence of a leukemic clone.

Family members of a proband with a known germline pathogenic variant(s) predisposing to monosomy 7. If a definitive germline pathogenic variant is identified in an affected family member (or if both definitive germline pathogenic variants are identified in a proband with an autosomal recessive predisposing disorder), molecular genetic testing can be performed in at-risk relatives to clarify their genetic risk:

  • In families with an autosomal dominant monosomy 7 predisposing syndrome, those identified as heterozygous for the pathogenic variant present in the affected family member and thus at high risk for developing myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) should seek consultation with a hematologist, oncologist, or HSCT specialist with expertise in monosomy 7 predisposition syndromes in order to develop an individualized treatment and surveillance plan.
  • In families with an autosomal recessive predisposing syndrome, those identified as having biallelic predisposing pathogenic variants and thus being at high risk for developing MDS or AML should seek consultation with a hematologist, oncologist, or HSCT specialist as recommended above.
  • In families with an X-linked monosomy 7 predisposing syndrome, males identified as hemizygous for the pathogenic variant present in the affected family member and thus at high risk for developing MDS or AML should seek consultation with a hematologist, oncologist, or HSCT specialist as recommended above.
  • Provided that genetic testing was performed using a germline, nonhematologic DNA sample, those without the monosomy 7-related pathogenic variant(s) defined as causal in the proband are no longer considered to be at increased risk for MDS or AML and thus may be discharged from hematologic surveillance.

Family members of a proband in whom the specific genetic cause of monosomy 7 predisposition has not been identified. Complete blood counts should be performed in all asymptomatic first-degree relatives (adults and children) of an individual with monosomy 7 predisposition syndrome in whom a germline pathogenic variant(s) has not been identified. If blood counts are normal, repeat of hematologic studies on a yearly basis is reasonable. If blood counts show cytopenias or RBC macrocytosis, these first-degree relatives should undergo bone marrow aspirate/biopsy studies including cytogenetic studies such as FISH and/or conventional cytogenetics to assess for presence of monosomy 7.

Related Genetic Counseling Issues

Family planning

  • The optimal time for determination of genetic risk and discussion of the availability of prenatal/preimplantation genetic testing is before pregnancy.
  • It is appropriate to offer genetic counseling (including discussion of potential risks to offspring and reproductive options) to young adults who are affected, are carriers, or at risk of being affected or carriers.

DNA banking. Because it is likely that testing methodology and our understanding of genes, allelic variants, and diseases will improve in the future, consideration should be given to banking DNA from probands in whom a molecular diagnosis has not been confirmed (i.e., the causative genetic alteration/s are unknown).

Prenatal Testing and Preimplantation Genetic Testing

Once the germline pathogenic variant(s) known to be associated with a monosomy 7 predisposition syndrome have been identified in an affected family member, prenatal and preimplantation genetic testing are possible.

Note: Monosomy 7 is not expected to be present in most fetal tissues sampled prenatally.

Differences in perspective may exist among medical professionals and within families regarding the use of prenatal testing. While most centers would consider use of prenatal testing to be a personal decision, discussion of these issues may be helpful.

Chapter Notes

Author Notes

North American Pediatric Aplastic Anemia Consortium
MDS Working Group
Website: www.napaac.org

Comprehensive Bone Marrow Failure Center, Cellular Therapy and Transplant Section
The Children's Hospital of Philadelphia
34th and Civic Center Blvd
Philadelphia, PA 19104
Websites: cbmfc.research.chop.edu; www.chop.edu/centers-programs/cellular-therapy-and-transplant-section

Center for Cancer and Blood Disorders
Children's Hospital Colorado
13123 East 16th Ave
Aurora, CO 80238
Website: www.childrenscolorado.org/doctors-and-departments/departments/cancer-and-blood-disorders

Bone Marrow Failure and Leukemia Predisposition Program
UT Southwestern/Children's Health
1935 Medical District Drive
Dallas, Texas 75235
Website: www.childrens.com/doctor-profile/kathryn-elyse-dickerson

Bone Marrow Failure Program
Experimental Hematology Division
St. Jude Children’s Research Hospital
262 Danny Thomas Place
Memphis, TN 38105-3678
Websites: www.stjude.org; www.stjude.org/samd9

Division of Pediatric Hematology and Oncology
Department of Pediatrics and Adolescent Medicine
Medical Center, Faculty of Medicine
University of Freiburg
Mathildenstraße 1, 79106 Freiburg, Germany
Website: www.uniklinik-freiburg.de

Revision History

  • 10 June 2021 (sw) Review posted live
  • 26 February 2021 (to) Original submission

References

Literature Cited

  • Aktas D, Koc A, Boduroglu K, Hicsonmez G, Tuncbilek E. Myelodysplastic syndrome associated with monosomy 7 in a child with Bloom syndrome. Cancer Genet Cytogenet. 2000;116:44–6. [PubMed: 10616531]
  • Araten DJ, Swirsky D, Karadimitris A, Notaro R, Nafa K, Bessler M, Thaler HT, Castro-Malaspina H, Childs BH, Boulad F, Weiss M, Anagnostopoulos N, Kutlar A, Savage DG, Maziarz RT, Jhanwar S, Luzzatto L. Cytogenetic and morphological abnormalities in paroxysmal nocturnal haemoglobinuria. Br J Haematol. 2001;115:360–8. [PubMed: 11703336]
  • Arber DA, Orazi A, Hasserjian R, Thiele J, Borowitz MJ, Le Beau MM, Bloomfield CD, Cazzola M, Vardiman JW. The 2016 revision to the World Health Organization classification of myeloid neoplasms and acute leukemia. Blood. 2016;127:2391–405. [PubMed: 27069254]
  • Babushok DV, Bessler M, Olson TS. Genetic predisposition to myelodysplastic syndrome and acute myeloid leukemia in children and young adults. Leuk Lymphoma. 2016;57:520–36. [PMC free article: PMC4798888] [PubMed: 26693794]
  • Bluteau O, Sebert M, Leblanc T, Peffault de Latour R, Quentin S, Lainey E, Hernandez L, Dalle JH, Sicre de Fontbrune F, Lengline E, Itzykson R, Clappier E, Boissel N, Vasquez N, Da Costa M, Masliah-Planchon J, Cuccuini W, Raimbault A, De Jaegere L, Adès L, Fenaux P, Maury S, Schmitt C, Muller M, Domenech C, Blin N, Bruno B, Pellier I, Hunault M, Blanche S, Petit A, Leverger G, Michel G, Bertrand Y, Baruchel A, Socié G, Soulier J. A landscape of germ line mutations in a cohort of inherited bone marrow failure patients. Blood. 2018;131:717–32. [PubMed: 29146883]
  • Bond J, Labis E, Marceau-Renaut A, Duployez N, Labopin M, Hypolite G, Michel G, Ducassou S, Boutroux H, Nelken B, Bertrand Y, Baruchel A, Petit A, Asnafi V, Leverger G, Preudhomme C, Macintyre E, Lapillonne H. Polycomb repressive complex 2 haploinsufficiency identifies a high-risk subgroup of pediatric acute myeloid leukemia. Leukemia. 2018;32:1878–82. [PubMed: 29950694]
  • Chen DH, Below JE, Shimamura A, Keel SB, Matsushita M, Wolff J, Sul Y, Bonkowski E, Castella M, Taniguchi T, Nickerson D, Papayannopoulou T, Bird TD, Raskind WH. Ataxia-pancytopenia syndrome is caused by missense mutations in SAMD9L. Am J Hum Genet. 2016;98:1146–1158. [PMC free article: PMC4908176] [PubMed: 27259050]
  • Churpek JE, Larson RA. The evolving challenge of therapy-related myeloid neoplasms. Best Pract Res Clin Haematol. 2013;26:309–17. [PMC free article: PMC3920194] [PubMed: 24507808]
  • Csillag B, Ilencikova D, Meissl M, Webersinke G, Laccone F, Narumi S, Haas O, Duba HC. Somatic mosaic monosomy 7 and UPD7q in a child with MIRAGE syndrome caused by a novel SAMD9 mutation. Pediatr Blood Cancer. 2019;66:e27589. [PubMed: 30565860]
  • Döhner H, Estey E, Grimwade D, Amadori S, Appelbaum FR, Büchner T, Dombret H, Ebert BL, Fenaux P, Larson RA, Levine RL, Lo-Coco F, Naoe T, Niederwieser D, Ossenkoppele GJ, Sanz M, Sierra J, Tallman MS, Tien HF, Wei AH, Löwenberg B, Bloomfield CD. Diagnosis and management of AML in adults: 2017 ELN recommendations from an international expert panel. Blood. 2017;129:424–47. [PMC free article: PMC5291965] [PubMed: 27895058]
  • Dumitriu B, Feng X, Townsley DM, Ueda Y, Yoshizato T, Calado RT, Yang Y, Wakabayashi Y, Kajigaya S, Ogawa S, Zhu J, Young NS. Telomere attrition and candidate gene mutations preceding monosomy 7 in aplastic anemia. Blood. 2015;125:706–9. [PMC free article: PMC4304114] [PubMed: 25406353]
  • Göhring G, Michalova K, Beverloo HB, Betts D, Harbott J, Haas OA, Kerndrup G, Sainati L, Bergstraesser E, Hasle H, Stary J, Trebo M, van den Heuvel-Eibrink MM, Zecca M, van Wering ER, Fischer A, Noellke P, Strahm B, Locatelli F, Niemeyer CM, Schlegelberger B. Complex karyotype newly defined: the strongest prognostic factor in advanced childhood myelodysplastic syndrome. Blood. 2010;116:3766–9. [PubMed: 20802024]
  • Göllner S, Oellerich T, Agrawal-Singh S, Schenk T, Klein HU, Rohde C, Pabst C, Sauer T, Lerdrup M, Tavor S, Stölzel F, Herold S, Ehninger G, Köhler G, Pan KT, Urlaub H, Serve H, Dugas M, Spiekermann K, Vick B, Jeremias I, Berdel WE, Hansen K, Zelent A, Wickenhauser C, Müller LP, Thiede C, Müller-Tidow C. Loss of the histone methyltransferase EZH2 induces resistance to multiple drugs in acute myeloid leukemia. Nat Med. 2017;23:69–78. [PMC free article: PMC6548550] [PubMed: 27941792]
  • Hasle H, Alonzo TA, Auvrignon A, Behar C, Chang M, Creutzig U, Fischer A, Forestier E, Fynn A, Haas OA, Harbott J, Harrison CJ, Heerema NA, van den Heuvel-Eibrink MM, Kaspers GJ, Locatelli F, Noellke P, Polychronopoulou S, Ravindranath Y, Razzouk B, Reinhardt D, Savva NN, Stark B, Suciu S, Tsukimoto I, Webb DK, Wojcik D, Woods WG, Zimmermann M, Niemeyer CM, Raimondi SC. Monosomy 7 and deletion 7q in children and adolescents with acute myeloid leukemia: an international retrospective study. Blood. 2007;109:4641–7. [PubMed: 17299091]
  • Hasle H, Niemeyer CM. Advances in the prognostication and management of advanced MDS in children. Br J Haematol. 2011;154:185–95. [PubMed: 21554264]
  • Higgins A, Shah MV. Genetic and genomic landscape of secondary and therapy-related acute myeloid leukemia. Genes (Basel). 2020;11:749. [PMC free article: PMC7397259] [PubMed: 32640569]
  • Inaba T, Honda H, Matsui H. The enigma of monosomy 7. Blood. 2018;131:2891–8. [PubMed: 29615405]
  • Jónsson H, Sulem P, Kehr B, Kristmundsdottir S, Zink F, Hjartarson E, Hardarson MT, Hjorleifsson KE, Eggertsson HP, Gudjonsson SA, Ward LD, Arnadottir GA, Helgason EA, Helgason H, Gylfason A, Jonasdottir A, Jonasdottir A, Rafnar T, Frigge M, Stacey SN, Th Magnusson O, Thorsteinsdottir U, Masson G, Kong A, Halldorsson BV, Helgason A, Gudbjartsson DF, Stefansson K. Parental influence on human germline de novo mutations in 1,548 trios from Iceland. Nature. 2017;549:519–22. [PubMed: 28959963]
  • Kardos G, Baumann I, Passmore SJ, Locatelli F, Hasle H, Schultz KR, Starý J, Schmitt-Graeff A, Fischer A, Harbott J, Chessells JM, Hann I, Fenu S, Rajnoldi AC, Kerndrup G, Van Wering E, Rogge T, Nollke P, Niemeyer CM. Refractory anemia in childhood: a retrospective analysis of 67 patients with particular reference to monosomy 7. Blood. 2003;102:1997–2003. [PubMed: 12763938]
  • Kuzmanovic T, Patel BJ, Sanikommu SR, Nagata Y, Awada H, Kerr CM, Przychodzen BP, Jha BK, Hiwase D, Singhal D, Advani AS, Nazha A, Gerds AT, Carraway HE, Sekeres MA, Mukherjee S, Maciejewski JP, Radivoyevitch T. Genomics of therapy-related myeloid neoplasms. Haematologica. 2020;105:e98–e101. [PMC free article: PMC7049337] [PubMed: 31413096]
  • Locatelli F, Strahm B. How I treat myelodysplastic syndromes of childhood. Blood. 2018;131:1406–14. [PubMed: 29438960]
  • Minelli A, Maserati E, Rossi G, Bernardo ME, De Stefano P, Cecchini MP, Valli R, Albano V, Pierani P, Leszl A, Sainati L, Lo Curto F, Danesino C, Locatelli F, Pasquali F. Familial platelet disorder with propensity to acute myelogenous leukemia: genetic heterogeneity and progression to leukemia via acquisition of clonal chromosome anomalies. Genes Chromosomes Cancer. 2004;40:165–71. [PubMed: 15138996]
  • Myers KC, Furutani E, Weller E, Siegele B, Galvin A, Arsenault V, Alter BP, Boulad F, Bueso-Ramos C, Burroughs L, Castillo P, Connelly J, Davies SM, DiNardo CD, Hanif I, Ho RH, Karras N, Manalang M, McReynolds LJ, Nakano TA, Nalepa G, Norkin M, Oberley MJ, Orgel E, Pastore YD, Rosenthal J, Walkovich K, Larson J, Malsch M, Elghetany MT, Fleming MD, Shimamura A. Clinical features and outcomes of patients with Shwachman-Diamond syndrome and myelodysplastic syndrome or acute myeloid leukaemia: a multicentre, retrospective, cohort study. Lancet Haematol. 2020;7:e238–e246. [PMC free article: PMC7984274] [PubMed: 31879230]
  • Nakano TA, Lau BW, Dickerson KE, Wlodarski M, Pollard J, Shimamura A, Hofmann I, Sasa G, Elghetany T, Cada M, Dror Y, Ding H, Allen SW, Hanna R, Campbell K, Olson TS. Diagnosis and treatment of pediatric myelodysplastic syndromes: A survey of the North American Pediatric Aplastic Anemia Consortium. Pediatr Blood Cancer. 2020;67:e28652. [PubMed: 32779892]
  • Narumi S, Amano N, Ishii T, Katsumata N, Muroya K, Adachi M, Toyoshima K, Tanaka Y, Fukuzawa R, Miyako K, Kinjo S, Ohga S, Ihara K, Inoue H, Kinjo T, Hara T, Kohno M, Yamada S, Urano H, Kitagawa Y, Tsugawa K, Higa A, Miyawaki M, Okutani T, Kizaki Z, Hamada H, Kihara M, Shiga K, Yamaguchi T, Kenmochi M, Kitajima H, Fukami M, Shimizu A, Kudoh J, Shibata S, Okano H, Miyake N, Matsumoto N, Hasegawa T. SAMD9 mutations cause a novel multisystem disorder, MIRAGE syndrome, and are associated with loss of chromosome 7. Nat Genet. 2016;48:792–7. [PubMed: 27182967]
  • Niemeyer CM, Baumann I. Classification of childhood aplastic anemia and myelodysplastic syndrome. Hematology Am Soc Hematol Educ Program. 2011;2011:84–9. [PubMed: 22160017]
  • Niemeyer CM, Flotho C. Juvenile myelomonocytic leukemia: who's the driver at the wheel? Blood. 2019;133:1060–70. [PubMed: 30670449]
  • Pabst T, Eyholzer M, Haefliger S, Schardt J, Mueller BU. Somatic CEBPA mutations are a frequent second event in families with germline CEBPA mutations and familial acute myeloid leukemia. J Clin Oncol. 2008;26:5088–93. [PubMed: 18768433]
  • Parker TM, Klaassen RJ, Johnston DL. Spontaneous remission of myelodysplastic syndrome with monosomy 7 in a young boy. Cancer Genet Cytogenet. 2008;182:122–5. [PubMed: 18406874]
  • Parrella S, Aspesi A, Quarello P, Garelli E, Pavesi E, Carando A, Nardi M, Ellis SR, Ramenghi U, Dianzani I. Loss of GATA-1 full length as a cause of Diamond-Blackfan anemia phenotype. Pediatr Blood Cancer. 2014;61:1319–21. [PMC free article: PMC4684094] [PubMed: 24453067]
  • Pastor VB, Sahoo SS, Boklan J, Schwabe GC, Saribeyoglu E, Strahm B, Lebrecht D, Voss M, Bryceson YT, Erlacher M, Ehninger G, Niewisch M, Schlegelberger B, Baumann I, Achermann JC, Shimamura A, Hochrein J, Tedgård U, Nilsson L, Hasle H, Boerries M, Busch H, Niemeyer CM, Wlodarski MW. Constitutional SAMD9L mutations cause familial myelodysplastic syndrome and transient monosomy 7. Haematologica. 2018;103:427–37. [PMC free article: PMC5830370] [PubMed: 29217778]
  • Peffault de Latour R, Soulier J. How I treat MDS and AML in Fanconi anemia. Blood. 2016;127:2971–9. [PubMed: 27020090]
  • Rentas S, Pillai V, Wertheim GB, Akgumus GT, Nichols KE, Deardorff MA, Conlin LK, Li MM, Olson TS, Luo M. Evolution of histomorphologic, cytogenetic, and genetic abnormalities in an untreated patient with MIRAGE syndrome. Cancer Genet. 2020;245:42–8. [PubMed: 32619790]
  • Richards S, Aziz N, Bale S, Bick D, Das S, Gastier-Foster J, Grody WW, Hegde M, Lyon E, Spector E, Voelkerding K, Rehm HL, et al. Standards and guidelines for the interpretation of sequence variants: a joint consensus recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. Genet Med. 2015;17:405–24. [PMC free article: PMC4544753] [PubMed: 25741868]
  • Rochowski A, Olson SB, Alonzo TA, Gerbing RB, Lange BJ, Alter BP. Patients with Fanconi anemia and AML have different cytogenetic clones than de novo cases of AML. Pediatr Blood Cancer. 2012;59:922–4. [PMC free article: PMC3407278] [PubMed: 22517793]
  • Rogers ZR, Nakano TA, Olson TS, Bertuch AA, Wang W, Gillio A, Coates TD, Chawla A, Castillo P, Kurre P, Gamper C, Bennett CM, Joshi S, Geddis AE, Boklan J, Nalepa G, Rothman JA, Huang JN, Kupfer GM, Cada M, Glader B, Walkovich KJ, Thompson AA, Hanna R, Vlachos A, Malsch M, Weller EA, Williams DA, Shimamura A. Immunosuppressive therapy for pediatric aplastic anemia: a North American Pediatric Aplastic Anemia Consortium study. Haematologica. 2019;104:1974–83. [PMC free article: PMC6886407] [PubMed: 30948484]
  • Sarasin A, Quentin S, Droin N, Sahbatou M, Saada V, Auger N, Boursin Y, Dessen P, Raimbault A, Asnafi V, Schmutz JL, Taïeb A, Menck CFM, Rosselli F, La Rochelle LD, Robert C, Sicre de Fontbrune F, Sébert M, Leblanc T, Kannouche P, De Botton S, Solary E, Soulier J. Familial predisposition to TP53/complex karyotype MDS and leukemia in DNA repair-deficient xeroderma pigmentosum. Blood. 2019;133:2718–24. [PMC free article: PMC6610036] [PubMed: 30914417]
  • Schratz KE, DeZern AE. Genetic predisposition to myelodysplastic syndrome in clinical practice. Hematol Oncol Clin North Am. 2020;34:333–56. [PMC free article: PMC7875473] [PubMed: 32089214]
  • Schwartz JR, Ma J, Kamens J, Westover T, Walsh MP, Brady SW, Robert Michael J, Chen X, Montefiori L, Song G, Wu G, Wu H, Branstetter C, Hiltenbrand R, Walsh MF, Nichols KE, Maciaszek JL, Liu Y, Kumar P, Easton J, Newman S, Rubnitz JE, Mullighan CG, Pounds S, Zhang J, Gruber T, Ma X, Klco JM. The acquisition of molecular drivers in pediatric therapy-related myeloid neoplasms. Nat Commun. 2021;12:985. [PMC free article: PMC7880998] [PubMed: 33579957]
  • Schwartz JR, Ma J, Lamprecht T, Walsh M, Wang S, Bryant V, Song G, Wu G, Easton J, Kesserwan C, Nichols KE, Mullighan CG, Ribeiro RC, Klco JM. The genomic landscape of pediatric myelodysplastic syndromes. Nat Commun. 2017a;8:1557.
  • Schwartz JR, Wang S, Ma J, Lamprecht T, Walsh M, Song G, Raimondi SC, Wu G, Walsh MF, McGee RB, Kesserwan C, Nichols KE, Cauff BE, Ribeiro RC, Wlodarski M, Klco JM. Germline SAMD9 mutation in siblings with monosomy 7 and myelodysplastic syndrome. Leukemia. 2017b;31:1827–30. [PMC free article: PMC5540771] [PubMed: 28487541]
  • Sébert M, Passet M, Raimbault A, Rahmé R, Raffoux E, Sicre de Fontbrune F, Cerrano M, Quentin S, Vasquez N, Da Costa M, Boissel N, Dombret H, Peffault de Latour R, Socié G, Itzykson R, Fenaux P, Soulier J, Adès L, Clappier E. Germline DDX41 mutations define a significant entity within adult MDS/AML patients. Blood. 2019;134:1441–4. [PubMed: 31484648]
  • Seiter K, Qureshi A, Liu D, Galvin-Parton P, Arshad M, Agoliati G, Ahmed T. Severe toxicity following induction chemotherapy for acute myelogenous leukemia in a patient with Werner's syndrome. Leuk Lymphoma. 2005;46:1091–5. [PubMed: 16019564]
  • Simon C, Chagraoui J, Krosl J, Gendron P, Wilhelm B, Lemieux S, Boucher G, Chagnon P, Drouin S, Lambert R, Rondeau C, Bilodeau A, Lavallée S, Sauvageau M, Hébert J, Sauvageau G. A key role for EZH2 and associated genes in mouse and human adult T-cell acute leukemia. Genes Dev. 2012;26:651–6. [PMC free article: PMC3323876] [PubMed: 22431509]
  • Skokowa J, Dale DC, Touw IP, Zeidler C, Welte K. Severe congenital neutropenias. Nat Rev Dis Primers. 2017;3:17032. [PMC free article: PMC5821468] [PubMed: 28593997]
  • Staines Boone AT, Chinn IK, Alaez-Versón C, Yamazaki-Nakashimada MA, Carrillo-Sánchez K, García-Cruz MLH, Poli MC, González Serrano ME, Medina Torres EA, Muzquiz Zermeño D, Forbes LR, Espinosa-Rosales FJ, Espinosa-Padilla SE, Orange JS, Lugo Reyes SO. Failing to make ends meet: the broad clinical spectrum of DNA ligase IV deficiency. Case series and review of the literature. Front Pediatr. 2019;6:426. [PMC free article: PMC6348249] [PubMed: 30719430]
  • Stanley N, Olson TS, Babushok DV. Recent advances in understanding clonal haematopoiesis in aplastic anaemia. Br J Haematol. 2017;177:509–25. [PMC free article: PMC5435524] [PubMed: 28107566]
  • Sun L, Babushok DV. Secondary myelodysplastic syndrome and leukemia in acquired aplastic anemia and paroxysmal nocturnal hemoglobinuria. Blood. 2020;136:36–49. [PMC free article: PMC7332901] [PubMed: 32430502]
  • Swaminathan M, Bannon SA, Routbort M, Naqvi K, Kadia TM, Takahashi K, Alvarado Y, Ravandi-Kashani F, Patel KP, Champlin R, Kantarjian H, Strong L, DiNardo CD. Hematologic malignancies and Li-Fraumeni syndrome. Cold Spring Harb Mol Case Stud. 2019;5:a003210. [PMC free article: PMC6371746] [PubMed: 30709875]
  • Takahashi K. Germline polymorphisms and the risk of therapy-related myeloid neoplasms. Best Pract Res Clin Haematol. 2019;32:24–30. [PubMed: 30927971]
  • Wimmer K, Etzler J. Constitutional mismatch repair-deficiency syndrome: have we so far seen only the tip of an iceberg? Hum Genet. 2008;124:105–22. [PubMed: 18709565]
  • Wlodarski MW, Hirabayashi S, Pastor V, Starý J, Hasle H, Masetti R, Dworzak M, Schmugge M, van den Heuvel-Eibrink M, Ussowicz M, De Moerloose B, Catala A, Smith OP, Sedlacek P, Lankester AC, Zecca M, Bordon V, Matthes-Martin S, Abrahamsson J, Kühl JS, Sykora KW, Albert MH, Przychodzien B, Maciejewski JP, Schwarz S, Göhring G, Schlegelberger B, Cseh A, Noellke P, Yoshimi A, Locatelli F, Baumann I, Strahm B, Niemeyer CM, et al. Prevalence, clinical characteristics, and prognosis of GATA2-related myelodysplastic syndromes in children and adolescents. Blood. 2016;127:1387–97. [PubMed: 26702063]
  • Wlodarski MW, Sahoo SS, Niemeyer CM. Monosomy 7 in pediatric myelodysplastic syndromes. Hematol Oncol Clin North Am. 2018;32:729–43. [PubMed: 30047423]
  • Wong JC, Bryant V, Lamprecht T, Ma J, Walsh M, Schwartz J, Del Pilar Alzamora M, Mullighan CG, Loh ML, Ribeiro R, Downing JR, Carroll WL, Davis J, Gold S, Rogers PC, Israels S, Yanofsky R, Shannon K, Klco JM. Germline SAMD9 and SAMD9L mutations are associated with extensive genetic evolution and diverse hematologic outcomes. JCI Insight. 2018;3:e121086. [PMC free article: PMC6124395] [PubMed: 30046003]
Copyright © 1993-2022, University of Washington, Seattle. GeneReviews is a registered trademark of the University of Washington, Seattle. All rights reserved.

GeneReviews® chapters are owned by the University of Washington. Permission is hereby granted to reproduce, distribute, and translate copies of content materials for noncommercial research purposes only, provided that (i) credit for source (http://www.genereviews.org/) and copyright (© 1993-2022 University of Washington) are included with each copy; (ii) a link to the original material is provided whenever the material is published elsewhere on the Web; and (iii) reproducers, distributors, and/or translators comply with the GeneReviews® Copyright Notice and Usage Disclaimer. No further modifications are allowed. For clarity, excerpts of GeneReviews chapters for use in lab reports and clinic notes are a permitted use.

For more information, see the GeneReviews® Copyright Notice and Usage Disclaimer.

For questions regarding permissions or whether a specified use is allowed, contact: ude.wu@tssamda.

Bookshelf ID: NBK571103PMID: 34110727

Views

Related information

  • PMC
    PubMed Central citations
  • PubMed
    Links to PubMed

Similar articles in PubMed

See reviews...See all...

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...