The prevalence of type 2 diabetes (T2D) has increased rapidly over the past decades.1 Successful management of T2D improves individuals’ life expectancy and quality.2 The basic principles of T2D management are based upon a combination of pharmacological treatments and lifestyle interventions.3 The medical approach includes the preferred first-line medication metformin and potentially second-line medications, e.g. glucagon-like peptide-1 (GLP-1) analogue, to manage blood glucose levels. This evidence concerns the gene GCG and type 2 diabetes mellitus.