Ataxia telangiectasia (AT), originally known as Louis-Bar Syndrome, is a rare autosomal recessive condition (prevalence: 40,000–1:300,000) [10], due to homozygous mutation of ATM gene associated to inability to protect cells from an excess of oxidative stress that will lead to an increased risk in the development of tumors and of cardiovascular diseases [1]. The gene discussed is ATM; the disease is Ataxia-telangiectasia.