GENETIC AND CELLULAR-FEATURES OF ATAXIA-TELANGIECTASIA

Ataxia telangiectasia (AT) is a developmental disorder in which many o rgan systems are affected. The children are recognized by a progressiv e cerebellar deterioration. The gene for AT has now been localized to a region of chromosome 11q22-23 of no more than 3Mb in size and its pr oduct appears to be involved directly or indirectly in some form of DN A recombination. Patients and their cells are unusually sensitive to i onizing radiation and various radiometric drugs. Observations on the p rogressive nature of the disorder, with loss of selected cells or fail ure to develop normally, might be compatible with the pathological eff ect of an inability to correctly regulate apoptosis in some cell linea ges. While this is an intriguing speculation there is, at present, no evidence for such a defect in AT.