With regards to the inter-ethnic differences, in all glucose tolerance states (T2DM, pre-DM, and NGT), the fasting total GLP-1 levels were significantly higher in Indians compared to Malays (30 ± 12.57 pmol/L vs. 22.95 ± 13.69 pmol/L, p<0.05; 25.48 ± 7.79 pmol/L vs. 19.41 ± 11.58 pmol/L, p<0.05; 19.39 ± 9.4 pmol/L vs. 13.82 ± 5.61 pmol/L, p<0.05), respectively. Here, GCG is linked to type 2 diabetes mellitus.