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Disease characteristics

Excerpted from the GeneReview: Bloom's Syndrome
Bloom’s syndrome (BSyn) is characterized by severe pre- and postnatal growth deficiency, highly characteristic sparseness of subcutaneous fat tissue throughout infancy and early childhood, and short stature throughout postnatal life that in most affected individuals is accompanied by an erythematous and sun-sensitive skin lesion of the face. Gastroesophageal reflux (GER) is common and very possibly responsible for infections of the upper respiratory tract, the middle ear, and the lung that occur repeatedly in most persons with BSyn. Although most affected individuals have normal intellectual ability, many exhibit a poorly defined (and little studied) learning disability. Women may be fertile, but menopause occurs unusually early; men are infertile. Serious medical complications that are much more common than in the general population and that also appear at unusually early ages are chronic obstructive pulmonary disease, diabetes mellitus resembling the adult-onset type, and cancer of a wide variety of types and anatomic sites. BSyn is very rare in all national and ethnic groups but is relatively less rare in Ashkenazi Jews.

Associated genes

Clinical features

  • Hirsutism
  • Hyperhidrosis
  • Decreased fertility in females
  • Cafe-au-lait spot
  • High pitched voice
  • Short stature
  • Sacral dimple
  • IgA deficiency
  • Hypopigmented skin patches
  • Narrow face
  • Microcephaly
  • Finger syndactyly
  • Agenesis of maxillary lateral incisor
  • Intrauterine growth retardation
  • Dolichocephaly
  • IgG deficiency
  • Cognitive impairment
  • Malar flattening
  • Irregular hyperpigmentation
  • Postnatal growth retardation
  • Recurrent respiratory infections
  • Micrognathia
  • Spotty hyperpigmentation
  • Spotty hypopigmentation
  • Diarrhea
  • Syndactyly
  • Azoospermia
  • Cryptorchidism
  • Decreased fertility
  • Sinusitis
  • Abnormality of the pinna
  • Protruding ear
  • Prominent nose
  • Cutaneous photosensitivity
  • Hand polydactyly
  • Intellectual disability, mild
  • Specific learning disability
  • Leukemia
  • Bronchiectasis
  • Acute leukemia
  • Lymphoma
  • Delayed skeletal maturation
  • IgM deficiency
  • Squamous cell carcinoma
  • Short nose
  • Abnormality of chromosome stability
  • Clinodactyly of the 5th finger
  • Facial telangiectasia in butterfly midface distribution
  • Type II diabetes mellitus
  • Chronic lung disease
  • Neoplasm of the gastrointestinal tract
  • Ichthyosis
  • Neoplasm of the skin
  • Reduced number of teeth
  • Cheekbone underdevelopment
  • Teleangiectasia of the skin
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Go to complete MedGen record for Bloom syndrome

Clinical resources

Practice guidelines

  • ACOG, 2009
    ACOG Committee Opinion No. 442: Preconception and prenatal carrier screening for genetic diseases in individuals of Eastern European Jewish descent.
  • ACMG, 2008
    Carrier screening in individuals of Ashkenazi Jewish descent.

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