Past studies have shown that in many patients with diabetes mellitus (DM), long-term insulin usage is associated with changes in the fatty tissue below the skin surface at injection sites, with the appearance of nodules or swollen/hardened areas.1–7 These lesions, called “lipohypertrophy” (LH or colloquially “lipos”), are not malignant and do not behave like tumors, but they can be unsightly and worrisome to patients. The gene discussed is INS; the disease is diabetes mellitus.