The CCTTT polymorphism in the NOS2A gene is associated with dementia with Lewy bodies

We report the analysis of the allele distribution of a (CCTTT)n pentanucleo tide repeat within the promoter region of the NOS2A gene in DNA samples fro m patients with autopsy confirmed Alzheimer's disease (AD) and dementia wit h Lewy bodies (DLB) type. A significant difference was observed in the alle lic distribution between the control group and the DLB group (chi(2) = 15.1 75, df = 5; p < 0.01), with an increased occurrence of the eight and nine r epeat alleles, and a marked under representation of the 11 repeat allele. G enotype frequencies in the DLB group also differed significantly from contr ols (p<0.012). These results suggest that variations in the NOS2A gene may predispose to the development of DLB. NeuroReport 11:297-299 (C) 2000 Lippi ncott Williams & Wilkins.