Our studies also highlighted significant eTWAS for T2D, including PCBD1, which is mutated in a syndrome that includes monogenic diabetes [31, 32], and encodes a co-factor of HNF1A, an established monogenic diabetes gene [33] (Additional file 1: Fig. S6c, Additional file 10: Table S9). The gene discussed is PCBD1; the disease is type 2 diabetes mellitus.