Friedreich's ataxia

Friedreich ataxia is the most common type hereditary ataxia and it is inherited in an autosomal recessive pattern. It is a slowly progressive ataxia with the age of onset in the first and second decades of life—usually below age 25. Some individuals with Friedreich ataxia may not develop symptoms until very late in life. Weakness of the extremities and loss of sensation become more prominent as the disease progresses. Skeletal deformities, including scoliosis, are also common. Friedreich’s Ataxia may also be associated with heart problems, including irregular heart beat and enlargement of the heart.

Most individuals with Friedreich ataxia have repeat expansions in both of their copies of the Friedreich ataxia gene. Some rare individuals may have a combination of a repeat expansion in one gene and a sequence change in their other copy of the gene. Carrier testing is available to family members. About 1-2% of the general population carries an abnormal gene for Friedreich ataxia, but these individuals do not have symptoms of Friedreich ataxia. It is only when both parents are carriers, the offspring will have a 25% chance of having the disease.