What are the genetic changes related to ataxia with vitamin E deficiency ?
Mutations in the TTPA gene cause ataxia with vitamin E deficiency. The TTPA gene provides instructions for making the -tocopherol transfer protein (TTP), which is found in the liver and brain. This protein controls distribution of vitamin E obtained from the diet (also called -tocopherol) to cells and tissues throughout the body. Vitamin E helps cells prevent damage that might be done by free radicals.  TTPA gene mutations impair the activity of the TTP protein, resulting in an inability to retain and use dietary vitamin E. As a result, vitamin E levels in the blood are greatly reduced and free radicals accumulate within cells. Nerve cells (neurons) in the brain and spinal cord (central nervous system) are particularly vulnerable to the damaging effects of free radicals and these cells die off when they are deprived of vitamin E. Nerve cell damage can lead to problems with movement and other features of ataxia with vitamin E deficiency.