A type of hearing impairment caused by an abnormal functionality of the cochlear nerve with congenital onset.

An abnormal reduction in the amount of pigmentation (reduced or absent) of skin, hair and eye (iris and retina).

Piebaldism is a rare autosomal dominant trait characterized by the congenital absence of melanocytes in affected areas of the skin and hair. A white forelock of hair, often triangular in shape, may be the only manifestation, or both the hair and the underlying forehead may be involved. The eyebrows and eyelashes may be affected. Irregularly shaped white patches may be observed on the face, trunk, and extremities, usually in a symmetrical distribution. Typically, islands of hyperpigmentation are present within and at the border of depigmented areas (summary by Thomas et al., 2004).

Any abnormality of the eye, including location, spacing, and intraocular abnormalities.