Association of DD Genotype of Insertion/Deletion Polymorphism of Angiotensin-Converting Enzyme Gene with Systemic Lupus Erythematosus and Lupus Nephropathy

Background: systemic lupus erythematosus (sle) is a multisystem disease with unknown etiology. we hypothesized that insertion/deletion (i/d) polymorphism of angiotensin-converting enzyme (ace) gene may influence the development and/or progression of sle and lupus nephritis. materials and methods: in a crass sectional case-control study, genomic dna from 106 sle patients and 103 healthy controls matched for sex, age, and ethnicity, were genotyped for the (i/d) polymorphism of ace gene by polymerase chain reaction (pcr). comparison of quantitative variants between two groups was assessed by student t-test and association between qualitative variables was analyzed by the chi-square or fisher exact tests. results: the frequency of dd genotype in sle patients was significantly higher than control group (25.5 % vs. 14 %), and the risk of sle was 2.2 times greater in subjects with dd genotype than the individual by di and ii genotypes (or, 2.2 [95% ci, 1.1 to 4.4]; p=0.023). the distribution of d allele in sle patients was significantly higher (p=0.021) compare to controls (47 and 36.4, respectively). the risk of nephropathy in sle patients with dd genotype was three times more than other genotypes (or), 3 [95% ci, 1.1 to 8]; p=0.027].conclusion: this study demonstrated that ace dd genotype acts as a risk factor on sle and lupus nephropathy in an iranian population.