Variants in the SOX10, EDN3, or EDNRB gene can cause Waardenburg syndrome type IV. Variants in the MITF or SNAI2 gene can cause Waardenburg syndrome type II. Waardenburg syndrome types I and III are caused by variants in the PAX3 gene. Variants in any of these genes disrupt the normal development of melanocytes, leading to abnormal pigmentation of the skin, hair, and eyes and problems with hearing. Melanocytes make a pigment called melanin, which contributes to skin, hair, and eye color and plays an essential role in the normal function of the inner ear. These genes are involved in the formation and development of several types of cells, including pigment-producing cells called melanocytes. Variants (also known as mutations) in the EDN3, EDNRB, MITF, PAX3, SNAI2, and SOX10 genes can cause Waardenburg syndrome. Type IV (also known as Waardenburg-Hirschsprung disease or Waardenburg-Shah syndrome) has signs and symptoms of both Waardenburg syndrome and Hirschsprung disease, an intestinal disorder that causes severe constipation or blockage of the intestine. Type III (sometimes called Klein-Waardenburg syndrome) includes abnormalities of the arms and hands in addition to hearing loss and changes in pigmentation. In addition, hearing loss occurs more often in people with type II than in those with type I. Types I and II have very similar features, although people with type I almost always have eyes that appear widely spaced and people with type II do not. There are four recognized types of Waardenburg syndrome, which are distinguished by their physical characteristics and sometimes by their genetic cause. The features of Waardenburg syndrome vary among affected individuals, even among people in the same family.
DO PEOPLE HAVE PURPLE EYES PATCH
Distinctive hair coloring (such as a patch of white hair or hair that prematurely turns gray) is another common sign of the condition. Sometimes one eye has segments of two different colors. People with this condition often have very pale blue eyes or different colored eyes, such as one blue eye and one brown eye.
The hearing loss is present from birth (congenital). Although most people with Waardenburg syndrome have normal hearing, moderate to profound hearing loss can occur in one or both ears. Waardenburg syndrome is a group of genetic conditions that can cause hearing loss and changes in coloring (pigmentation) of the hair, skin, and eyes.
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