In a look-up in our results of CpGs and DMRs identified in previous studies to be associated with maternal glucose metabolism or with adult type 2 diabetes, we found that one CpG, cg1680945 at MDN1, known to be related to adult type 2 diabetes was also significantly associated with maternal early-pregnancy insulin concentrations (effect estimate = − 3.3 × 10−3 (SE 1.1 × 10−3), p value = 2.2 × 10−3) [27]. This evidence concerns the gene INS and type 2 diabetes mellitus.