Association of manganese superoxide dismutase gene polymorphism (V16A) with diabetic macular edema in Korean type 2 diabetic patients.
This study was designed to investigate whether V16A polymorphism of the manganese superoxide dismutase (Mn-SOD) gene is associated with the development of type 2 diabetes mellitus and with progression of diabetic retinopathy (DR) and diabetic macular edema (DME). We simultaneously analyzed insertion/deletion polymorphism of the angiotensin-converting enzyme (ACE) gene in the 16th intron to avoid its confounding effect. A total of 192 nondiabetic subjects and 304 type 2 diabetic patients were included in the study. Diabetic retinopathy was classified as nonretinopathy, nonproliferative retinopathy, and proliferative retinopathy. Diabetic macular edema was defined as thickening of the retina and/or hard exudates within a 1-disk diameter of the center of the macula. Diabetic macular edema was further classified into focal, diffuse, and ischemic types. The A allele frequency of the Mn-SOD gene was not different between nondiabetic and type 2 diabetic subjects, between the normotensive and hypertensive groups, between the DR (-) and DR (+) groups, and among the stages of DR. In the DR (+) group, the DME (+) group had a lower A allele frequency than that of the DME (-) group. In the DME (+) group, focal, diffuse, and ischemic types were found in 8, 23, and 6 patients, respectively. The A allele frequency of each type was 0.188, 0.109, and 0.0. The D allele frequency of the angiotensin-converting enzyme gene did not differ in any of the comparisons. Clinical and laboratory parameters of the A allele carriers were not different from those of the noncarriers except for the prevalence of hypertension and DME. Hypertension, diabetic duration, and insulin therapy were related to DR. The A allele, hypertension, and insulin therapy were associated with DME. In conclusion, our results suggest that V16A polymorphism of the Mn-SOD gene is not related to the development of diabetes and progression of DR, but is associated with DME in Korean type 2 diabetic patients.
Lee
Seong Jin
SJ
Department of Endocrinology and Metabolism, College of Medicine, Hallym University, ChunCheon Sacred Heart Hospital, Kangwon-Do 200-704, South Korea. leesj@hallym.ac.kr
Choi
Moon Gi
MG
D000328:Adult; D000368:Aged; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000201:enzymology; D003930:Diabetic Retinopathy / Q000201:enzymology / Q000209:etiology* / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008269:Macular Edema / Q000201:enzymology / Q000209:etiology* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000235:genetics; D011110:Polymorphism, Genetic; D012307:Risk Factors; D013482:Superoxide Dismutase / Q000235:genetics*; D041623:Tomography, Optical Coherence
D013482:Superoxide Dismutase; D007703:Peptidyl-Dipeptidase A