Rs6235 was found to be associated with decreasing fasting glucose levels and increased HOMA-B [15], [26], while rs6232 was associated with decreased circulating post-prandial glucose and elevated glucagon levels in a Danish population-based study [27], and discordantly associated with decreased fasting insulin levels and reduced insulin sensitivity in German adults with increased risk of T2D [26]. This evidence concerns the gene GCG and type 2 diabetes mellitus.