Angiotensin II type 2 receptor gene polymorphisms and serum angiotensin-converting enzyme level in Egyptian children with systemic lupus erythematosus

Background There are no reports about the association of angiotensin II type 2 receptor (AT2R) gene polymorphisms and susceptibility to systemic lupus erythematosus (SLE) in children. Objective The objective of this research is to study AT2R gene polymorphisms in exon 3 (C1593A) and intron 1 (A1675G) in Egyptian children with SLE and its correlation with disease manifestations and serum angiotensin-converting enzyme (ACE) level. Methods Typing of AT2R gene polymorphisms was conducted in 123 children with SLE in comparison with 100 healthy controls using the restriction fragment length polymorphism method. Results Significant differences were found between SLE patients and controls for A-containing genotypes (CA + AA) and A-allele frequencies of AT2R in exon 3 (C1593A) (p = 0.01, odds ratio (OR) = 2.5, 95% confidence interval (CI) = 1.3-5.05; p = 0.01, OR = 2.2, 95% CI = 1.2-4.1, respectively). G-containing genotypes (AG + GG) and G allele of AT2R in intron 1 (A1675G) were more frequent in SLE patients compared to controls (p = 0.01, OR = 2.3, 95% CI = 1.2-4.5; p = 0.02, OR = 2.1, 95% CI = 1.2-3.7, respectively). Serum ACE level was significantly higher in SLE patients than in controls (p < 0.001). There was no association between AT2R gene polymorphisms and ACE level in serum. Moreover, there was no association between AT2R gene polymorphisms and SLE clinical manifestations. Conclusion AT2R gene polymorphisms can be considered risk factors for SLE development in Egyptian children.