Variations that cause disease are called mutations and A-T results from a defective gene, the ATM gene (for ataxia telangiectasia, mutated), first identified in 1995.
Ataxia means poor coordination, and the telangiectasia are tiny, red spider blood vessels which develop in A-T patients, especially on the whites of the eyes and on the surface of the ears.
Establishing a diagnosis for ataxia telangiectasia is most difficult in very young children, primarily because the full-blown syndrome is not yet apparent.
As of 2004, there is no cure for ataxia telangiectasia, thus specific therapy is not available, and treatment is largely supportive.
Any family touched by ataxia telangiectasia is forever affected.