These genes showed a significant (p-value = 1.53 × 10−2) enrichment in their protein-protein interactions (PPI) with each other according to STRING (Additional file 2: Fig. S3) [63], including seven interactions between genes significantly associated with the cross-trait shared architecture of T2D and PAD in Europeans and genes associated with the cross-trait shared architecture of T2D and PAD in East Asians (e.g., interactions of STARD10 [European-specific] with AP3S2 [East Asian-specific], and KCNJ11 [European-specific] with KCNQ1 [East Asian-specific]). The gene discussed is AP3S2; the disease is type 2 diabetes mellitus.