title: Polymorphism of renin-angiotensin system genes in IgA nephropathy.
abstract: OBJECTIVE
  Individuals are prone to disease because of certain disease-susceptible genes. The angiotensin I-converting enzyme (ACE) gene insertion/deletion (I/D), the angiotensinogen (AGT) gene, M235T, and the angiotensin II type 1 receptor (ATR) gene, A1166C, polymorphisms have been associated with IgA nephropathy (IgAN) and its progression. Several studies on Caucasians and Japanese patients have reported contradictory results. We determined these polymorphisms in 118 Chinese patients with IgAN and 94 healthy Chinese subjects to assess their clinical impact.
  
  
  METHODS
  Genotyping was performed with DNA isolated from peripheral leucocytes, polymerase chain reaction amplification of the polymorphic sequence, restriction enzymes digestion, and separation and identification of DNA fragments. Clinical data at renal biopsy and final status on renal function were determined from patients' records.
  
  
  RESULTS
  Comparing all IgAN patients with controls, AGT and ATR genotype distributions were similar, whereas there was a significant increase in the ACE DD genotype (P < 0.05). When comparing patients with end-stage renal failure (IgAN-ESRF) and those without (IgAN-nonESRF), there was no difference among the three gene polymorphisms. In contrast, there were significant differences in higher male prevalence (P < 0.05), increased serum creatinine at presentation (P < 0.05), more sclerosis (P < 0.01) and higher tubulointerstitial lesion score (P < 0.001) in the IgAN-ESRF group.
  
  
  CONCLUSIONS
  Among the ACE, AGT and ATR gene polymorphisms, only the DD genotype may predispose the individual to IgAN in the Chinese population. None are significant for prognosticating ESRF.
authors.affiliation: Department of Renal Medicine, Singapore General Hospital, Singapore. grmwkt@sgh.com.sg
authors.forename: Keng-Thye
authors.initials: KT
authors.lastname: Woo
authors.forename: Yeow-Kok
authors.initials: YK
authors.lastname: Lau
authors.forename: Lina Hl
authors.initials: LH
authors.lastname: Choong
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhao
authors.forename: Hwee-Boon
authors.initials: HB
authors.lastname: Tan
authors.forename: Stephanie
authors.initials: S
authors.lastname: Fook-Chong
authors.forename: Eng-King
authors.initials: EK
authors.lastname: Tan
authors.forename: Hui-Kim
authors.initials: HK
authors.lastname: Yap
authors.forename: Kok-Seng
authors.initials: KS
authors.lastname: Wong
mesh_terms: D000328:Adult; D002681:China; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005922:Glomerulonephritis, IGA / Q000150:complications / Q000235:genetics*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000235:genetics; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012084:Renin-Angiotensin System / Q000235:genetics*