Piebaldism

Description

Piebaldism is a condition characterised by the absence of cells called melanocytes in certain areas of the skin and hair. Melanocytes produce the pigment melanin, which contributes to hair, eye, and skin colour. The absence of melanocytes leads to patches of skin and hair that are lighter than normal. Approximately 90 percent of affected individuals have a white section of hair near their front hairline (a white forelock). The eyelashes, the eyebrows, and the skin under the forelock may also be unpigmented.

People with piebaldism usually have other unpigmented patches of skin, typically appearing symmetrically on both sides of the body. There may be spots or patches of pigmented skin within or around the borders of the unpigmented areas.

In most cases, the unpigmented areas are present at birth and do not increase in size or number. The unpigmented patches are at increased risk of sunburn and skin cancer related to excessive sun exposure. Some people with piebaldism are self-conscious about the appearance of the unpigmented patches, which may be more noticeable in darker-skinned people. Aside from these potential issues, this condition has no effect on the health of the affected individual.

Inheritance patterns

The source lists the following possible inheritance patterns: Autosomal dominant. More than one pattern can apply in different cases.

Related genes

• SNAI2

• KIT

Other names

PBT

Piebald trait