Our single-nucleotide variant rs2237447 (chr7:50640147) maps to the GRB10 gene very close to the GRB10 SNP rs10248619 that was significantly associated with fasting glycaemic traits and IR in a GWAS study of Manning et al.15 Additionally, another risk allele at rs2237457 was shown to be associated with T2D and glucose excursion during oral glucose tolerance test in the Old Order Amish Study.44GRB10 interacts with insulin receptors and inhibits their signalling45 and hence is functionally well connected to the traits in our study. Here, GRB10 is linked to type 2 diabetes mellitus.