In multivariable logistic regression analysis, agriculture occupation (OR, 1.2; 95% CI: 1.0–1.4; p = 0.026), diabetic neuropathy (OR, 1.4; 95% CI: 1.1–1.6; p = 0.001), diabetic foot (OR, 1.6; 95% CI: 1.2–2.0; p = 0.001), PVA > 0.3 (OR, 1.2; 95% CI: 1.1–1.4; p = 0.001), duration of diabetes (OR, 1.7; 95% CI: 1.6–1.8; p < 0.001), OHA compared with diet (OR, 2.5; 95% CI: 2.1–3.0; p < 0.001), Insulin compared with diet (OR, 3.4; 95% CI: 2.6–4.5; p < 0.001) and both (OHA and insulin) compared with diet (OR, 5.0; 95% CI: 3.8–6.6; p < 0.001) were significantly associated with DR. The gene discussed is INS; the disease is diabetes mellitus.