The condition known as albinism has been known since antiquity. In fact, the biblical Noah is claimed by some to have been an albino. Multiple types have been described and all are caused by mutations in genes that are involved in the synthesis of pigment.
This type of albinism is characterized by decreased pigmentation in the eyes, hair and skin. There are secondary changes in the retinas (light sensing tissue) of the eye that lead to dysfunction of the rods and cones resulting in loss of vision. The condition is present at birth as white skin and hair. The colored part of the eye (iris) is generally pale but may darken with age. The normal color of the inside of the eye is not present and appears ‘blond’. The eyes usually have a to-and-fro motion (nystagmus) beginning at 3-4 months of age and are unable to fixate on a target. Depth perception is often defective. Vision is stable in the range of 20/50 to 20/200. Sensitivity to light (photophobia) can be marked.
People with a subtype of this condition may have some darkening of the skin, hair, and iris as they grow older but the vision does not improve. Some individuals develop freckles and other pigmented skin spots. There is an increased risk of skin cancer from sun exposure.
Type II is the most common type of oculocutaneous albinism and is the most likely type among people of African descent and in Native American populations. It is inherited in an autosomal recessive pattern which requires the presence of two mutations. Parents who carry a single mutation have normal pigmentation. Two parents who each carry the mutation can expect on average that 25% of their children will have type II oculocutaneous albinism.
The absence of pigmentation at birth suggests a diagnosis of albinism but gene studies are required to document the type. An ophthalmological examination can be helpful in the diagnosis as well as in determination of the nature of the visual defect. Reduced vision can often be slightly improved with glasses and tinting of lenses may be helpful outdoors. Low vision aids are often useful. Sun protection is advised to reduce the risk of skin cancer.