We grouped the glucagon receptor variants the following way: (1) the SNP G40S, previously associated with non-insulin-dependent diabetes, hypertension and adiposity [21–23], but normal cAMP signalling and reduced β-arrestin signalling [5], (2) the missense variants V368M, R378C, R225H, R308W and D63N were grouped as ‘cAMP LoF’ based on previous research [5], and (3) variants annotated as frameshift or stop-codon gained were grouped as ‘Frameshift’ variants (ESM Table 2). This evidence concerns the gene GCGR and type 1 diabetes mellitus.