Pendred Syndrome

Pendred syndrome is an inherited disorder leading to bilateral sensorineural hearing loss. Children who are born with Pendred syndrome may begin to lose their hearing at birth or by the time they are three years old. Usually, their hearing will worsen over time. The loss of hearing often happens suddenly, although some individuals will later regain some hearing. Eventually, some children with Pendred syndrome become totally deaf. Other abnormalities of the inner ear are also common in Pendred syndrome. Some affected individuals have problems with balance caused by dysfunction of the part of the inner ear that helps maintain the body's balance and orientation. By late childhood through adulthood, some individuals develop a goiter, which is an enlargement of the thyroid gland. In most cases, this enlargement does not cause the thyroid gland to malfunction. Intellect is not affected in individuals with Pendred Syndrome. Pendred syndrome is caused by pathogenic variants in the SLC26A4 gene.

Pendred syndrome is inherited in an autosomal recessive manner. This type of inheritance requires the presence of two copies of a pathogenic variant in the gene for a person to have the genetic disease. Both parents must be carriers of a pathogenic variant in the gene in order to be at risk to have an affected child. The child must inherit a pathogenic variant from each carrier parent in order to be affected. There is a 1 in 4 chance that a baby will inherit two mutated copies of the gene and be affected when both parents are carriers.

There are generally no signs or symptoms associated with being a carrier for Pendred syndrome. However, the risk to have a child affected with these disorders is increased. Testing of reproductive partners is recommended for carriers of Pendred syndrome.

The exact occurrence of Pendred syndrome is not known, although it is estimated to account for 1-8% of all congenital deafness cases. Variation is observed among different populations.

Genetics Home Reference: Pendred Syndrome (http://ghr.nlm.nih.gov/)
Genetic Alliance: Pendred Syndrome (http://www.diseaseinfosearch.org/)

OMIM [Pendred Syndrome: 274600] (http://www.ncbi.nlm.nih.gov/omim)
Pendred Syndrome (http://www.ncbi.nlm.nih.gov/books/NBK1116/)

• Full gene sequencing