The Ataxia telangiectasia (A-T) syndrome is a multisystem disorder exhibiting a complex array of clinical features for which there is no effective therapy. The earliest and most debilitating aspect of this disease is progressive ataxia resulting from neurodegeneration of the cerebellum. Several lines of evidence suggest a potential function for ATM in the maintenance of cellular homeostasis, and disruptions in functional ATM appear to result in alterations cholesterol homeostasis. This association may provide some insight into the neurodegenerative aspect of this disease. Cholesterol homeostasis is particularly significant in the central nervous system (CNS) with several neurodegenerative disorders involving disturbances in cholesterol homeostasis. The goal of this thesis was to attempt to establish a potential relationship between ATM and cholesterol homeostasis. As well it was hoped the establishment of a mechanism for such a relationship may help contribute to the establishment of therapies for this debilitating aspect of A-T...