Albinism

Albinism is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair and eyes due to absence or defect of tyrosinase, a copper-containing enzyme involved in the production of melanin.


People with albinism also usually have a number of eye conditions, such as:

• problems with eyesight – they may benefit from wearing glasses, although these can't usually fully correct vision
• nystagmus (involuntary eye movements)
• photophobia (sensitivity to light)

There are two main types of albinism:

• oculocutaneous albinism (OCA) – the most common type that affects the skin, hair and eyes
• ocular albinism (OA) – a rarer type that mainly affects the eyes

These two types are caused by different genetic faults, and they can be divided into many further sub-types that are caused by a number of different faulty genes.

The inheritance condition is happened when X-linked recessive conditions often don't affect females because females have two X chromosomes, one of which will be normal and can usually compensate for the mutated chromosome. However, females who inherit the mutation will become carriers.

If a male inherits the mutation from his mother (males receive a Y chromosome from their fathers), he will not have a normal copy of the gene and will develop albinism.
When a mother is a carrier of an X-linked mutation, each daughter they have has a one in two chance of becoming a carrier and each son they have has a one in two chance of having albinism.
When a father has an X-linked condition, his daughters will become carriers of the mutation.