How common is A-T?
Ataxia-Telangiectasia respects no racial, economic, geographic or educational barriers. Both males and females are equally affected. Epidemiologists estimate the frequency of A-T between 1 in 40,000 and 1 in 100,000 births. But it is believed that many children with A-T, particularly those who die at a young age, are never properly diagnosed. Therefore, this disease may actually be much more common. In the U.S., A-T is the second most common recessive ataxia of childhood, Friedreich's Ataxia being the most common but usually occurs at a somewhat later age than A-T. Most every person "carries" a defective gene of some sort. 1 or 2 people out of EVERY 100 people are unknowingly carrying the defective A-T gene (ATM).
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