When analyzing the variants previously reported to associate with type 2 diabetes in the paper by Mahajan et al. [15], the variant in the EYA2 locus was associated with higher 30 min plasma glucagon levels during the OGTT, after correction for multiple testing (rs6063048 Beta 0.145, SE 0.038, P = 1.2 × 10–4, see Additional file 1: Table S1). This evidence concerns the gene GCG and type 2 diabetes mellitus.