Ocular albinism is a genetic disorder where a patient's eyes lack melanin, leading to vision problems. People often associate albinism with pale skin, white hair, and reddish to pink eyes, but people with ocular albinism typically have a skin coloration close to that seen in the rest of their family, and often have colored hair and some color in their eyes. Patients may have blue, brown, or green eyes, depending on their genetics. In people with a very mild form of this condition, ocular albinism may not pose any problems, while others may be legally blind and could have other symptoms like being hard of hearing or deaf.
This condition is X-linked. The two genes known to have a connection with ocular albinism can be found on the X chromosome, and the condition is much more common in males. For women to have this condition, it is necessary to inherit two copies of the defective genes, and this is relatively unusual. Most women with the genes are simply carriers and don't experience any pigmentation changes in their eyes.
Over 10 forms of ocular albinism are known, the result of genes combining and expressing in a variety of ways. Patients with this condition may have some missing pigmentation in the iris of the eye, but the real problem lies in the retina, specifically the highly sensitive area of the retina known as the fovea. The fovea does not develop completely because of the reduced melanin, and the patient will have vision problems as a result. Some people have near perfect visual acuity, while others may have very poor vision without correction.
People with ocular albinism may have abnormalities in the optic nerve as well. Some experience nystagmus, uncontrolled jerking movements of the eyes, and strabismus, where the eyes do not move in synchronicity with each other. Patients are also typically sensitive to bright light and may need to be careful about wearing sunglasses to protect their eyes.
Ocular albinism does not grow worse over time. When a doctor diagnoses the patient, she can perform an evaluation to determine the extent of the problem. The patient's vision should remain stable, and the use of corrective lenses can help to address the symptoms. People with this condition who worry about passing it on to their children can meet with a genetic counselor to discuss the situation. The genetics behind this condition are complex, and it's possible for children to be born with no defective genes at all or a very mild form of the condition.
