There was also no difference between the two groups in the inhibition of glucagon secretion by hyperglycemia (C-peptide + group: 0.72 [95% CI: 0.60–0.86] fold, vs. C-peptide − group: 0.73, [95% CI: 0.58–0.91] fold, P = 0.92) or by GLP-1 (C-peptide positive group: 0.83 [95% CI: 0.66–1.05] fold, vs. C-peptide negative group: 0.86 [95% CI: 0.77–0.96] fold, P = 0.76). This evidence concerns the gene GCG and Hyperglycemia.