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Borgaonkar DS. Chromosomal Variation in Man: A Catalog of Chromosomal Variants and Anomalies: Online NLM Version [Internet]. Bethesda (MD): National Center for Biotechnology Information (US); 1975-.

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Chromosomal Variation in Man: A Catalog of Chromosomal Variants and Anomalies: Online NLM Version [Internet].

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  • Austin-Ward E D, castillo S, Dragnic Y, Sanz P, Salazar S, Knoll J H M.: Clinical findings in a patient mosaic for a supernumerary ring chromosome 20. AJMG 91:171-174, 2000. [PubMed: 10756336]
    The 2 year 8 month old patient was being evaluated because of psychomotor retardation, facial anomalies, and speech delay.
    Aberration: Ring chromosome
  • Bastepe M, Lane A H, Juppner H.: Paternal uniparental isodisomy of chromosome 20q--and the resulting changes in GNAS1 methylation--as a possible cause of pseudohypoparathyroidism. AJHG 68:1283-1289, 2001. [PMC free article: PMC1226109] [PubMed: 11294659]
    Patient K-1 was 5 years 11 months old.
    Aberration: Uniparental disomy
    MIM#: 300800
    Index Terms: GNAS1,Pseudohypoparathyroidism
  • Begleiter M L, Lim C, Thorp J A: Mosaic isochromosome 20q. Prenat. Diag. 11:278, 1991. [PubMed: 1896415]
    Normal new born infant was reported.
    Aberration: Isochromosome
    No band
  • Callen D F, Eyre H J, Ringenbergs M L, Freemantle C J, Woodroffe P, Haan E A: Chromosomal origin of small ring marker chromosomes in man: characterization by molecular genetics. AJHG 48:769-782, 1991. [PMC free article: PMC1682952] [PubMed: 2014800]
    Case 10.
    The patient was 7 years old. He had dysmorphic features and short stature.
    There is an error in the paper with regard to the sex designation of this patient. On page 773 this patient is described as a male and the photograph appears to corroborate this description, whereas in Table 2 case 10 is erroneously described as a female. This error was brought to my attention on 2-17-1999, by Harshida Shah,MD, who was collating data on r(20) cases.
    Aberration: Ring chromosome
    No band
  • Chodirker B N, Jenkins R: Mosaic isochromosome 20q found on amniocentesis with normal outcome. Prenat. Diag. 10:469-472, [PubMed: 2235906]
    Aberration: Isochromosome
    No band
  • Cooper C, Fifer A, Ocraft K: A further case of prenatally detected mosaic isochromosome 20q. Prenat. Diag. 13:226, 1993. [PubMed: 8506224]
    A normal healthy boy was delivered at term. Mosaicism restricted to amniotic cultures.
    Aberration: Isochromosome
    No band
  • Deloukas P, Matthews L H, Ashurst J, Burton J, Gilbert J G R, Jones M, Stavrides G, Almeida J P, Babbage A K, Bagguley C L, Bailey J, Barlow K F, Bates K N, Beard L M, Beare D M, Beasley O P, Bird C P, Blakey S E, Bridgeman A M, Brown A J, Buck D, Burrill W, Butler A P, Carder C, Carter N P, Chapman J C, Clamp M, Clark G, Clark L N, Clark S Y, Clee C M, Clegg S, Cobley V E, Collier R E, Connor R, Corby N R, Coulson A, Coville G J, Deadman R, Dhami P, Dunn M, Ellington A G, Frankland J A, Fraser A, French L, Garner P, Grafham D V, Griffiths M N D, Gwilliam R, Hall R E, Hammond S, Harley J L, Heath P D, Ho S, Holden J L, Howden P J, Huckle E, Hunt A R, Hunt S E, Jekosch K, Johnson C M, Johnson D, Kay M P, Kimberley A M, King A, Knights A, Laird G K, Lawlor S, Lehvaslaiho M H, Leversha M, Lloyd C, Lloyd D M, Lovell J D, Marsh V L, Martin S L, Mcconnachie L J, Mclay K, McMurray A A, Milne S, Mistry D, Moore M J F, Mullikin J C, Nickerson T, Oliver K, Parker A, Patel R, Pearce T A V, Peck A I, Phillimore B J C T, Prathalingam S R, Plumb R W, Ramsay H, Rice C M, Ross M T, Scott C E, Sehra H K, Shownkeen R, Sims S, Skuce C D, Smith M L, Soderlund C, Steward C A, Sulston J E, Swann M, Sycamore N, Taylor R, Tee L, Thomas D W, Thorpe A, Tracey A, Tromans A C, Vaudin M, Wall M, Wallis J M, Whitehead S L, Whittaker P, Willey D L, Williams L, Williams S A, Wilming L, Wray P W, Hubbard T, Durbin R M, Bentley D R, Beck S, Rogers J.-The Wellcome Trust Sanger Institute. : The DNA sequence and comparative analysis of human chromosome 20. Nature 414:865-871, 2001. [PubMed: 11780052]
    Hattori M, Taylor T D.: The human genome: part three in the book of genes. Nature 414:854-855, 2001. [PubMed: 11780043]
    An editorial commentary (by Hattori and Taylor) on the complete sequence of chromosome 20 is presented.
    The finished sequence comprises 59,187,298 base pairs (bp) and represents 99.4% of the euchromatic DNA. A single contig of 26 megabases (Mb) spans the entire short arm, and five contigs separated by gaps totalling 320 kb span the long arm of this metacentric chromosome. 727 genes and 168 pseudogenes were annotated in the sequence.
    Index Terms: DNA sequence chromosome 20
  • Djalali M, Barbi G, Grab D: A further case of mosaic isochromosome 20q detected in amniotic fluid cells. Prenat. Diag. 12:71-72, 1992. [PubMed: 1557315]
    Amniotic fluid:mos46,XX/46,XX,i(20q).&Fetal blood:46,XX.
    Phenotypically the infant was found to have normal features.
    Aberration: Isochromosome
    No band
  • Donnenfeld A E, Kershner M A: Significance of mosaic isochromosome 20q on amniocentesis. AJMG 47:1196-1197, 1993. [PubMed: 8291555]
    Patient 1
    mos46,XX[58% from 15 colonies]/,46,XX,-20,+i(20q)[42%]-amniotic fluid.
    Patient is developmentally normal at 2 years of age. She had a nasofrontal protrusion (benign dermoid cyst at craniotomy) at 8 months of age.
    Patient 2
    mos46,XX(2 colonies)/46,XX,-20,+i(20q)(6 colonies).
    The infant is normal at 9 months of age.
    Aberration: Isochromosome
    No band
  • Eggermann T, Mergenthaler S, Eggermann K, Albers A, Linnemann K, Fusch C, Ranke M B, Wollmann H A.: Identification of interstitial maternal uniparental disomy (UPD)(14) and complete maternal UPD(20) in a cohort of growth retarded patients. JMG 38:86-89, 2001. [PMC free article: PMC1734807] [PubMed: 11158171]
    Eggermann T, Zerres K, Eggermann K, Moore G, Wollmann H A.: Uniparental disomy: clinical indications for testing in growth retardation. Europ. J. Pediat. 161:305-312, 2002. [PubMed: 12029448]
    Further cases with isolated IUGR should be screened for UPD20 to estimate its frequency and phenotypic consequences.
    Case 2: Referred at 17 months because of growth retardation.
    He showed macrocephaly, strabismus, and clinodactyly of both hands.
    Aberration: Uniparental disomy
    No band
  • Gosden C, Nicolaides K H, Rodeck C H: Fetal blood sampling in investigation of chromosome mosaicism in amniotic fluid cell culture. Lancet i:613-617, 1988. [PubMed: 2894549]
    46,XX,dic(20)/47,XX,+dic(20)/69,XXX,dic(20)+derivatives,dic(20).,This karyotypic interpretation is different from that of the authors.
    Aberration: Dicentric chromosome
    No band
  • Gray B A, Bent-Willimas A, Wolff D J, Zori R T.: A non-sex chromosome marker in a patient with an atypical Ullrich-Turner phenotype and mosaicism of 46,X,mar/46,XX. Clin. Genet. 60:73-76, 2001. [PubMed: 11531974]
    46,X,mar.ish der(20)(D20Z1+)[35]/46,XX[15].
    The patient was 12 years old with pervasive developmental delay with mild to moderate autism.
    Index Terms: Ullrich-Turner phenotype atypical
  • Hsu L Y F, Yu M T, Richkind K E, Van Dyke D L, Crandall B F, Saxe D F, Khodr G S, Mennuti M, Stetten G, Miller W A, Priest J H.: Incidence and significance of chromosome mosaicism involving an autosomal structural abnormality diagnosed prenatally through amniocentesis: a collaborative study. Prenat. Diag. 16: 1-28, 1996. [PubMed: 8821848]
    CasesVIb-9 and 10 from Miller W (93-3789; and 91-0113).
    Normal male liveborn.
    Data on 19 cases are summarised; mostly all were normal liveborns.
    Aberration: Isochromosome
    No band
  • Kershner M A, Donnenfeld A E: A second report of normal outcome with mosaic isochromosome 20q found on amniocentesis. Prenat. Diag. 11:487, 1991. [PubMed: 1754569]
    Aberration: Isochromosome
    No band
  • Kratzer P G, Golbus M S, Schonberg S A, Heilbron D C, Taylor R N: Cytogenetic evidence for enhanced selective miscarriage of trisomy 21 pregnancies with advancing maternal age. AJMG 44:657-663, 1992. [PubMed: 1481829]
    Aberration: Isochromosome
    No band
  • Priest J H, Sanders T L, Brown A L, May K M: Prenatal diagnosis of mosaic isochromosome 20q. Prenat. Diag. 11:137, 1991. [PubMed: 2062821]
    There was no abnormality present at birth in the twins.
    Initial studies on amniotic fluid cultures were done by Paula Berry. Mosaicism was present in multiple cultures.,Comment has been made about the involvement of chromosome 20 in placental mosaicism.
    Aberration: Isochromosome
    Index Terms: Placenta ... mosaicism
    No band
  • Richkind K E, Mahoney M J, Evans M I, Willner J, Douglass R: Prenatal diagnosis and outcomes of five cases of mosaicism for an isochromosome of 20q. Prenat. Diag. 11:371-376, 1991. [PubMed: 1924178]
    Cases DC, SF, KK, KR, and SW.
    mos46,XX or XY/47,XX or XY,+i(20q).
    The development of all five children has been normal. It is suggested that the abnormal cell line is of extrafetal origin.
    Aberration: Isochromosome
    Index Terms: Extrafetal
    No band
  • Romain D R, Whyte S, Callen D F, Eyre H J: A rare heteromorphism of chromosome 20 and reproductive loss. J. Med. Genet. 28:477-478, 1991. [PMC free article: PMC1016959] [PubMed: 1895318]
    Use of biotinylated alphoid probe D20Z1 confirmed the presence of amplified sequences adjacent to the centromere.
    Aberration: Marker chromosome
    No band
  • Storto P, Diehn T.: An additional report of prenatal detection of mosaic isochromosome 20q at amniocentesis. Prenat. Diag. 17:89-90, 1997. [PubMed: 9021836]
    Amniocytes-mos46,XY,i(20q)[47 colonies]/46,XX[41 colonies].
    The child is reported to be within normal limits at 23 months and no further testing has been undertaken.
    Aberration: Isochromosome
    No band
  • Viersbach R, Engels H, Gamerdinger U, Hansmann M.: Delineation of supernumerary marker chromosomes in 38 patients. AJMG 76:351-358, 1998. [PubMed: 9545101]
    Viersbach R, Engels H, Schwanitz G.: Identification of supernumerary der(20) chromosomes by FISH in three patients. AJMG 70:278-283, 1997. [PubMed: 9188666]
    Patient 1:
    mos46,XY/47,XY,+mar.ish r(20)(D20Z1+,wcp20+)de novo
    At the age of 20 months, the patient is normal but has an isolated syndactyly type 1 of toes 2 and 3.
    Patient 2:
    mos46,XX/47,XX,+der(20)(D20Z1+,wcp20-)de novo
    At the age of 20 months, the child was within normal limits.
    Detected prenatally and pregnancy was continued.
    Patient 3:
    mos46,XY/47,XY,+r(20)(D20Z1+,wcp20+)/,48,XY,+r(20),+r(20)de novo
    The infant was evaluated at the age of 2 1/2 years, because of a complex heart defect, cyanosis and clubbed fingers.
    At the age of 4 years, there was global delayed development in gross motor, fine motor, speech and social skills.
    Aberration: Ring chromosome
    Chromosomal Aneuploidy: 20+
Copyright © 2011-2013, Digamber Borgaonkar.
Bookshelf ID: NBK106613


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