A study by Valentina Moskvina, Cardiff University School of Medicine, Wales, UK, and colleagues, examined the genetic overlap between Parkinson’s and Alzheimer’s. The study was published online on 5 August in JAMA Neurology.
Data sets from the UK, Germany, France and the USA were used to perform a combined genome-wide association analysis. The analysis of Alzheimer’s included 3,177 patients with Alzheimer’s and 7,277 control individuals, and the genome-wide association analysis for Parkinson’s included 5,333 patients with the disease and 12,298 control individuals. The genetic analyses resulted in no significant evidence that supported the presence of loci (location of gene) that were associated with increased risk for both Parkinson’s and Alzheimer’s, according to the study results.
“Our findings therefore imply that loci that increase the risk of both Parkinson’s and Alzheimer’s 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. However further studies of Parkinson’s patients with evidence of dementia and Alzheimer’s patients with other neurological symptoms, which were excluded from the original genome-wide studies, could reveal genetic risk factors that increase risk to the shared clinical symptoms.