HLA-DRB1 and gestational diabetes: In support of our finding, a previous study reported an association between GDM and a CpG site located in gene MHC, class II, DR beta (HLA-DRB) [13], an important paralog of HLA-DMB; and alterations in DNAm of the MHC region in placentas from mothers with GDM [25, 33], as well as in cord blood of offspring from mothers with GDM [24].