What is (are) Pendred syndrome ?
Pendred syndrome is a condition usually characterized by sensorineural hearing loss in both ears (bilateral) and euthyroid goiter (enlargement of the thyroid gland with normal thyroid gland function). The amount of hearing loss varies among affected people. In many cases, significant hearing loss is present at birth. In other cases, hearing loss does not develop until later in infancy or childhood. Some people have problems with balance caused by dysfunction of the part of the inner ear that helps with balance and orientation (the vestibular system). Pendred syndrome is inherited in an autosomal recessive manner. Mutations in 3 genes are currently known to cause the condition (SLC26A4, FOXI1, and KCNJ10) and are found in about half of affected people. Other genes responsible for the condition have not yet been identified.