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Oculocutaneous albinism (OCA)

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A newborn has white hair, very pale skin that doesn't tan, and pink-blue irides. Pediatric ophthalmology finds nystagmus, foveal hypoplasia, and reduced visual acuity (~20/100). Parents are unaffected; the child has no abnormal bleeding or recurrent infections.

AR; multiple genes corresponding to OCA subtypes:

SubtypeGenePigment phenotypeNotes
OCA1ATYR (null)No pigment ever, white hair lifelongMost severe; tyrosinase activity absent
OCA1BTYR (residual)Some pigment by adulthoodTyrosinase partially functional
OCA2OCA2 (P gene)Pigment develops over timeMost common worldwide; founder variants in African populations
OCA3TYRP1Reddish/brown hair; "rufous albinism"Most common in sub-Saharan Africa
OCA4SLC45A2VariableCommon in Asian populations
  • Skin/hair: pale white to cream; minimal-to-no tanning; lifetime sun-related skin cancer risk
  • Eyes:
    • Nystagmus (early infancy)
    • Iris transillumination
    • Foveal hypoplasia (low visual acuity, 20/60 to 20/200)
    • Optic nerve mis-routing (excessive crossing at chiasm): diagnostic on VEP
    • Strabismus, photophobia
  • No bleeding, no immune deficiency: these distinguish OCA from syndromic forms
  • Clinical (hypopigmentation + characteristic eye findings + foveal hypoplasia on OCT)
  • Molecular gene panel (OCA1–4 plus syndromic forms)
  • Hermansky-Pudlak syndrome (HPS): OCA + platelet storage pool defect (bleeding) + pulmonary fibrosis. Multiple subtypes; HPS-1 is severe, common in Puerto Ricans.
  • Chediak-Higashi syndrome: OCA + immunodeficiency + giant cytoplasmic granules + accelerated lymphoproliferative phase.
  • Griscelli syndrome: silvery hair + immunodeficiency or neurologic disease (depending on subtype).

If a patient with albinism has bleeding, immune issues, or pulmonary symptoms, the diagnosis is NOT OCA.

  • Skin protection: lifelong sun protection, annual dermatology screening for skin cancer
  • Vision: low-vision aids, refraction, classroom accommodations; tinted lenses for photophobia
  • Surveillance: rule out HPS in any patient with bruising; order platelet electron microscopy
  • Genetic counseling: AR, ~25% recurrence risk

"OCA = Only Cutaneous + Anatomical-eye": pure OCA has no platelet, immune, or pulmonary findings. Anything beyond skin and eyes points to a syndromic albinism (HPS, Chediak-Higashi, Griscelli).

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