Pendred syndrome is a condition where the body has difficulty making a protein called pendrin. Pendrin is important for the normal functions of the inner ear and thyroid.
People with Pendred syndrome often have severe deafness, which is usually there from birth, but how severe it is can vary. Some may lose their hearing quickly when they’re babies or young kids, while others might have a steady level of hearing loss that doesn’t get worse over time. The inner-ear issues in Pendred syndrome can also affect a person’s balance. Some individuals might also notice their thyroid getting bigger (called a goiter), showing up as a large swelling at the base of the neck. This usually happens after a hearing loss diagnosis and can occur at any time in a person’s life. Even though Pendred syndrome typically doesn’t mess with thyroid function, goiters can make it hard to swallow and breathe because they put pressure on the esophagus and windpipe. Treatment for Pendred syndrome focuses on dealing with hearing loss early on, including using hearing aids for kids with the condition. Cochlear implants, a kind of device, seem promising for bringing back some hearing for people with severe to total deafness.
Pendred syndrome is caused by pathogenic (disease-causing) variants in the SLC26A4 gene and exhibits autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance to have a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background. For example, individuals of Ashkenazi Jewish descent have a 1 in 50 chance to be a carrier.