Although the prior literature has no direct evidence linking TAS1R3 single-nucleotide polymorphisms to T2D and obesity risks [31], studies on gastric tissue [34] and pancreatic-β cells [27] have shown diminished TAS1R3 expression in obese and T2D patients, suggesting that TAS1R3 activity may be altered in obesity/T2D pathogenesis. Here, TAS1R3 is linked to obesity due to melanocortin 4 receptor deficiency.