Waardenburg Syndrome is a group of conditions that involve deafness and pale skin, hair, and eye colour and is passed down through families.
The disease can be passed on through a faulty gene by only one parent to the child. This is why it is usually referred to be inherited as an autosomal dominant trait.
When there are mutations in the EDN3, EDNRB, MITF, PAX3, SNAI2, and SOX10 genes, this syndrome occurs. The function of these genes is to form and develop several types of cells, which include melanocytes (pigment-producing cells).
Melanocytes are responsible for creating a pigment known as melanin, which gives colour to your eyes, hair and skin. It also has an important part to play in the normal functioning of inner ear. If there are any changes in these genes, the normal development of melanocytes gets disrupted which in term leads to abnormal pigmentation of the skin, hair, and eyes and problems with hearing. Also, these genes are important for the development of nerve cells in the large intestine. Mutations in any of these genes result in hearing loss, changes in pigmentation, and intestinal problems related to Hirschsprung disease.
Changes in the PAX3 gene cause type I and III Waardenburg syndrome whereas type II is caused by mutations in MITF and SNAI2 genes and type IV is caused by SOX10, EDN3, or EDNRB genes mutations.
Most people with this syndrome have an affected parent and only a small percentage of cases detect new mutations in the gene. These people may not have a family history of Waardenburg syndrome.
Sometimes it is found in affected people with type II and type IV of this syndrome to have inherited the disease through an autosomal recessive pattern. This means that both copies of the gene in each cell have mutations. In many such cases, one off the parent may be carrying one copy of the mutated gene but may not experience any signs and symptoms.
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