Parkin variants in North American Parkinson's disease: cases and controls.

We report on an evaluation of coding variants within the parkin gene to assess their frequency in a North American clinical series of 313 Parkinson's disease (PD) cases and 192 unrelated controls. We hypothesized that the carrier frequency of parkin coding mutations, exon deletions, or duplications may be greater in PD cases. However, point mutations and exonic deletions/duplications, reported previously as pathogenic in homozygous or compound heterozygous individuals, occurred in both cases and controls with similar frequencies (3.8% in cases, 3.1% in controls). Furthermore, only stratified subanalyses detected any genetic association between the V380L common coding polymorphism and PD. We discuss the implication of parkin mutations for Parkinson's disease from this population perspective.