A literature search was conducted to comprehensively review the various articles and case reports highlighting the importance of the proper insulin injection technique practices being carried out by the people with T1DM globally across the different regions. This article encompasses the review of multiple original articles, review articles, and case reports from the research databases and search engines such as PubMed, Scopus, ScienceDirect, EMBASE, Cochrane Library, Google Scholar, and BioMed Central. This evidence concerns the gene INS and type 1 diabetes mellitus.