Considering the substantial body of evidence already published regarding the enhancing effect of INGAP-PP on β-cell function and mass in in vivo and ex vivo animal models, along with promising results from clinical trials (such as reduced HbA1c levels in T2D and increased C-peptide in T1D), we hypothesize that INGAP-PP or a more tolerable analog holds potential as a tool for diabetes treatment. This evidence concerns the gene REG3A and type 1 diabetes mellitus.