The extrapolation of the technology platforms developed for insulin to GLP-1 and other peptide drugs, for example, analogues of GIP and of amylin, a 37-amino-acid peptide co-secreted with insulin from pancreatic beta cells, provide an important example of how the discovery of insulin indirectly has impacted modern medicine beyond providing a life-saving replacement therapy for people with type 1 diabetes. This evidence concerns the gene GIP and type 1 diabetes mellitus.