For example, two single nucleotide polymorphisms (SNPs) of ADRB2 (Gly16Arg and Gln27Glu) and one of ADRB1 (Gly389Arg) were associated with obesity and T2DM in a Swedish and a Finnish study [5-8]. Here, ADRB2 is linked to obesity due to melanocortin 4 receptor deficiency.