Data sources
For both colocalization and Mendelian randomization (MR) analyses, data were obtained from publicly available summary statistics of genome-wide association studies (GWAS) outlined in Table 1. We selected Parkinson’s disease, cognitive performance, lacunar stroke and MRI quantified white matter hyperintensity as outcomes to represent common neurodegenerative conditions. Lacunar stroke and MRI-quantified white matter hyperintensity, both which are well-recognised features of vascular dementia, were used as surrogate outcomes in the absence of available GWAS for vascular dementia.