It has been proposed that there is an increased frequency of glucosidase-beta mutations in Lewy body disorders. Our comprehensive DNA sequencing approach found a small number of glucosidase-beta mutations in 101 neuropathologically defined Lewy body disease cases (3%) compared to 99 healthy post-mortem controls (1%); odds ratio 3.0 (95% CI: 0.3-29, p=0.3). All three affected carriers were classified as diffuse Lewy body disease (n=3/50; 6%). Our study suggests glucosidase-beta variants have a limited role in susceptibility to Lewy body disease in North America.