The vulnerable, ventrally located DaN subtype—selectively depleted in PD samples—from the SNpc were most strongly enriched for the expression of PD risk genes identified by genome-wide association studies (GWAS), including SNCA, MAPT, GAK, WNT3, and IGSF9B [33, 35], suggesting that the presence of these genetic risk factors, and possibly their altered activity in these vulnerable neurons, comprises an inherent risk that influences their survival in PD. This evidence concerns the gene SNCA and Parkinson disease.