Gene symbol Gene ID Gene location Sequence variant rs ID of the polymorphism Diabetes type Retinopathy type DOID Population Number of samples (cases/controls) Statistical significance Method Main result of the study Type of study Reference PMID PPARG 5468 3p25.2 / / T1DM PDR 13207 Japan 17 (12 PDR, 5 controls) Quantitative real-time PCR, ELISA, immunohistochemistry analysis Higher expression of PPARG in PDR versus controls Expression study Katome et al. [20 ] 25468312 PPARG 5468 3p25.2 rs1801282 rs1801282 T2DM DR, PDR 8947, 13207 Chinese 792 T2DM (448 DR, 344 diabetes without DR) OR (95% CI) dominant model GG: 1.40 (0.85-2.29); PCR-LDR No significant association between polymorphisms in the PPARG gene and DR or PDR Case-control study Zhang et al. [22 ] 25274455 PPARG 5468 3p25.2 Pro12Ala / T2DM DR 8947 Caucasian 5170 (2720 DR cases, 2450 controls) Caucasian subgroup ( Statistics Protective effect of Pro12Ala on DR in T2DM with ethnic differences Meta-analysis Ma et al. [23 ] 22993484 PPARG 5468 3p25.2 C1341T rs3856806 T2DM DR 8947 Chinese 500 T2DM (247 DR cases, 253 controls) OR Quantitative PCR rs1805192 minor allele (Ala) of PPARG is significantly associated with lower DR risk; combined effect of Ala-BMI interaction between polymorphism and overweight on DR Case-control study Wang et al. [24 ] 26885119 PPARG 5468 3p25.2 rs1801282 (c.34C>G, Pro12Ala) rs1801282 T2DM DR, PDR 8947, 13207 Pakistani 573 (189 DR, 193 DNR, 200 controls) PCR-RFLP Protective role of the 12Ala polymorphism against PDR in T2DM Case-control study Tariq et al. [25 ] 23559865 PPARG 5468 3p25.2 p.Pro12Ala / T2DM DR 8947 Indian 1325 (717 DR, 608 T2DM without DR) Real-time PCR No significant association Case-control study Kaur et al. [21 ] 27427939 PPARA 5465 22q13.31 rs4253778 rs4253778 T2DM DR 8947 Chinese Han 812 (402 DR, 410 control) Quantitative PCR Association between rs1800206 minor (V) allele and lower risk for DR; interaction between rs1800206 and abdominal obesity Case-control study Qi et al. [26 ] 26671228
