An important observation comes from a retrospective study of 2501 adults with T2D in the United Kingdom, with an HbA1c ≥64 mmol/mol (≥8.0%), which showed that 25% of the cohort did not have their treatment intensified to include insulin for at least 1.8 years, and 50% were not initiated on insulin therapy for almost 5 years after not achieving the target HbA1c range.5 This evidence concerns the gene INS and type 2 diabetes mellitus.