An autosomal recessive inherited disorder characterized by choreoathetosis beginning in childhood, progressive CEREBELLAR ATAXIA; TELANGIECTASIS of CONJUNCTIVA and SKIN; DYSARTHRIA; B- and T-cell immunodeficiency, and RADIOSENSITIVITY to IONIZING RADIATION. Affected individuals are prone to recurrent sinobronchopulmonary infections, lymphoreticular neoplasms, and other malignancies. Serum ALPHA-FETOPROTEINS are usually elevated. (Menkes, Textbook of Child Neurology, 5th ed, p688) The gene for this disorder (ATM) encodes a cell cycle checkpoint protein kinase and has been mapped to chromosome 11 (11q22-q23).

Synonyms: Ataxia Telangiectasia, Louis-Bar Syndrome, Ataxia Telangiectasia Syndrome, Syndrome, Louis-Bar, Louis Bar Syndrome, Ataxia-Telangiectasia, Syndrome, Ataxia Telangiectasia, Telangiectasia, Cerebello-Oculocutaneous