Familial Dysautonomia

Familial Dysautonomia is an inherited disorder that affects the development and survival of specific types of cells in the nervous system. People who are born with familial dysautonomia have signs of the disease at birth. The nervous system of a person affected with familial dysautonomia will gradually get worse over time as well. Children affected with this disorder typically have low muscle strength. They can also have stomach and digestive problems, episodes of vomiting, and can have trouble breathing. They can have problems related to perception of pain and temperature. Children affected with familial dysautonomia will typically have delayed developmental milestones such as walking and speech. Individuals with familial dysautonomia have a decreased life expectancy when compared to people who do not have this disorder although medical surveillance and care may help to improve some symptoms and overall condition of life. Familial dysautonomia is caused by pathogenic variants in the IKBKAP gene.

Familial Dysautonomia 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 familial dysautonomia. However, the risk to have a child affected with familial dysautonomia is increased. Testing of reproductive partners is recommended for carriers of familial dysautonomia.

Familial dysautonomia is common in the Ashkenazi Jewish population, occurring in about 1 in 3700 newborns. This disorder is extremely rare in the general population.

Genetics Home Reference: Familial Dysautonomia (http://ghr.nlm.nih.gov/)
Dysautonomia Foundation (http://www.familialdysautonomia.org/)

Gene Reviews: Familial Dysautonomia (http://www.ncbi.nlm.nih.gov/books/NBK1116/)

• Full gene sequencing