ATAXIA TELANGIECTASIA: An Inherited Human Disorder Involving Hypersensitivity to Ionizing Radiation and Related DNA-Damaging Chemicals

Abstract

This review is primarily devoted to ataxia telangiectasia - a complex multisystem disorder exhibiting many characteristics, both in vivo and in vitro, expected of an ionizing radiation analogue of XP. The recent upsurge of investigative interest in the cytotoxic, cytogenetic, and DNA repair properties of cultured AT cells after radiation treatment was prompted by the disclosure that AT patients are hypersensitive to conventional radiotherapy administered for treatment of malignancy. Our main aims in the review are fourfold: (a) to summarize the pertinent clinical and laboratory characteristics of AT, (b) to speculate on the basic DNA repair defect in AT cells, (c) to postulate on the role of faulty repair in the development of the disease, and finally (d) to identify gaps in our knowledge and recommend future directions.