Genetic Disorder Reference Sheet: ATM Pathogenic Variants

An estimated 1%–2% of adults have one pathogenic ataxia telangiectasia mutated (ATM) gene variant (heterozygous) and are considered carriers. People who are homozygous (two altered copies) have ataxia-telangiectasia (A-T), a hereditary condition that often appears in childhood and is characterized by progressive neurologic problems that lead to difficulty walking and an increased risk for developing various malignancies. Children with A-T may begin staggering and appear unsteady (ataxia) shortly after learning to walk.