A study by Valentina Moskvina, Ph.D., of the Cardiff University School of Medicine, Wales, United Kingdom, and colleagues, examined the genetic overlap between Parkinson disease (PD) and Alzheimer disease (AD).
Data sets from the United Kingdom, Germany, France and the United States were used to perform a combined genome-wide association analysis (GWA). The GWA study of AD included 3,177 patients with AD and 7,277 control patients, and the GWA analysis for PD included 5,333 patients with PD and 12,298 control patients. The gene-based analyses resulted in no significant evidence that supported the presence of loci (location of gene) that were associated with increased risk for both PD and AD, according to the study results.
"Our findings therefore imply that loci that increase the risk of both PD and AD are not widespread and that the pathological overlap could instead be 'downstream' of the primary susceptibility genes that increase the risk of each disease," the study concludes.
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JAMA Neurol. Published online August 5, 2013. doi:10.1001/.jamaneurol.2013.448