An autosomal recessive subtype of tyrosinase positive oculocutaneous albinism commonly seen in Puerto Rico is the Hermansky-Pudlak syndrome. Another autosomal recessive subtype of oculocutaneous albinism is the Ch diak-Higashi syndrome. Here, patients may have a silvery sheen to their skin, and blue to brown irides. Normal tyrosinase activity within hair bulbs shows increased susceptibility to infection, hepatosplenomegaly, lymphadenopathy and a predisposition to development of a lymphoma-like condition. Ocular albinism, in contrast to oculocutaneous albinism, exhibits pigmentary dilution due to abnormalities in melanosome synthesis rather than inadequate melanization.
Ocular albinism is transmitted through either an X-linked or autosomal recessive mode.
The hair and skin of the ocular albino tends to show a much greater pigmentation than that of the oculocutaneous albino, often falling into a normal pigmentation range. The uveal pigmentation of the ocular albino is variable and may range from very hypopigmented to a nearly normal pigmentation level. Both ocular and oculocutaneous albinism exhibit a hypoplastic macula. Orderly retinal morphogenesis depends on the organizing influence of the adjacent retinal pigment epithelium. The insufficient uveal pigmentation and poor development of the RPE in the albinotic patient provides a developmentally unstable substrate for normal retinal organization.