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BTI - GeneReviews#. Oculocutaneous albinism type 2 (OCA2) is characterized by hypopigmentation of the skin and hair and the characteristic ocular changes found in ALL types of albinism, including nystagmus; reduced iris pigment with iris translucency; reduced retinal pigment with visualization of the choroidal blood vessels on ophthalmoscopic examination; foveal hypoplasia associated with reduction in visual acuity; and misrouting of the optic nerve fiber radiations at the chiasm,associated with strabismus, reduced stereoscopic vision, and altered visual evoked potentials (VEP). Individuals with OCA2 are usually recognized within thefirst three to six months of life because of the ocular features of visual inattention, nystagmus, and strabismus. Vision is stable to slowly improving after early childhood until mid- to late teens, and no major change or loss of established visual acuity occurs related to the albinism. The amount of cutaneous pigmentation in OCA2 ranges from minimal to near-normal compared to others of the same ethnic and family backgrounds. Newborns with OCA2 almost always have lightly pigmented hair, brows, and lashes, with color ranging from light yellow to blondto brown. Hair color may darken with age but does not vary substantially from adolescence to adulthood. Brown OCA, initially identified in Africans and African Americans with light brown hair and skin, is part of the spectrum of OCA2. The diagnosis of OCA2 is based on clinical findings. OCA2 (previously called P) is the only gene in which mutations are known to cause oculocutaneous albinism type2. Treatment of manifestations: Correction of refractive errors with spectacles or (when age-appropriate) contact lenses may improve visual acuity; strabismus surgery can be considered for either functional (improved peripheral fusion) or cosmetic reasons. Hats with brims and dark glasses or transition lenses often reduce discomfort in bright light (photodysphoria). Protection from sun exposurewith appropriate skin-covering clothing and sunscreens prevents burning, consequent skin damage, and the enhanced risk of skin cancer. Skin cancer, including a slightly enhanced risk for cutaneous melanoma, is treated as for thegeneral population. Surveillance: Annual ophthalmologic examination to reassess refractive errors, strabismus and/or face turn; annual to biennial skin examination for evidence of sun-related skin damage and/or pre-cancerous or cancerous lesions. Agents/circumstances to avoid: Prolonged sun exposure. OCA2 is inherited in an autosomal recessive manner. The parents of a proband are obligate heterozygotes and therefore carry one mutant allele. Heterozygotes (carriers) are asymptomatic. At conception, each sib of an affected individual has a 25% chanceof being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier. Carrier testing for at-risk relatives and prenatal testing for pregnancies at increased risk are possible ifthe disease-causing mutations in an affected family member are known.#CI- Copyright (c) 1993-2013, University of Washington, Seattle. ALL rights reserved.#FED - Pagon, Roberta A#ED- Pagon RA#FED - Adam, Margaret P#ED- Adam MP#FED - Bird, Thomas D#ED- Bird TD#FED - Dolan, Cynthia R#ED- Dolan CR#FED - Fong, Chin-To#ED- Fong CT#FED - Stephens, Karen#ED- Stephens K#FAU - Lewis, Richard Alan