<prompt> Which of the following is true regarding ataxia telangiectasia?It is X linked recessive diseaseIt is autosomal recessive disorderIt is associated with increased levels of IgMNone of the above  <response>: Ans. b It is autosomal recessive disorderRef: Robbins 9th ed p 315Several rare autosomal recessive cancer syndromes have been described that are characterized by hypersensitivity to certain kinds of DNA-damaging agents, such as ionizing radiation Bloom syndrome and ataxia-telangiectasia, or DNA cross-linking agents, such as many chemotherapeutic drugs Fanconi anemia. The phenotype of these diseases is complex and includes, in addition to predisposition to cancer, features such as neural symptoms ataxia- telangiectasia, bone marrow aplasia Fanconi anemia, and developmental defects Bloom syndrome. 