Multivariate logistic regression mode showed that apoC-II/apoC-III and apoB/non–HDL-C (p < 0.001) as well as apoE/apoC-II (p = 0.001) were the independent risk factors for the occurrence and severity of DR—apopA-I and apoA-II are protective factors for DR—after controlling for the duration of DM, HbA1c, fasting glucose, and LPA. This evidence concerns the gene APOC2 and diabetes mellitus.