B2M and Parkinson disease: Unexpectedly, we did not find any overlap between our DEG and PD familial genes or those genes located within regions of high LD to SNPs associated with the disease by recent PD meta‐analyses.28 However, we did find 4 increased genes that have been identified as GWAS hits of modest significance for sporadic PD by other smaller studies—3 higher among the dorsal SNpc neurons: MMRN2 (multimerin 2),48ANXA1,49 and B2M (beta‐2‐microglobulin)50; and 1 higher among the ventral SNpc neurons: AGTR (angiotensin II receptor type 1).51