title: Genetic polymorphisms influence the steroid treatment of children with idiopathic nephrotic syndrome.
abstract: BACKGROUND
  Idiopathic nephrotic syndrome (INS) is the most frequent type of nephrotic syndrome that occurs in children. Its response to treatment with steroids varies. The aim of this study was to analyze the correlation between steroid metabolism-related genes and the response to steroid treatment.
  
  
  METHODS
  The patient cohort comprised 74 children with INS, of whom were 58 steroid-sensitive (SS) cases and 16 steroid-resistant (SR) cases. The genetic polymorphisms analyzed were those of the CYP3A5 gene (A6986G) and ABCB1 gene (C1236T, G2677T/A, and C3435T), and the polymorphisms between SS and SR children were compared.
  
  
  RESULTS
  C1236T in ABCB1 was associated with steroid resistance in INS children [odds ratio (OR) 2.65, 95 % confidence interval (CI) 1.01-6.94; p = 0.042] The frequency of the T allele was significantly higher in SR subjects than in SS subjects (0.81 vs. 0.62, respectively). A6986G in CYP3A5 showed a trend of association, but this association did not reach statistical significance (OR 2.63, 95 % CI 0.94-7.37; p = 0.059). No significant correlation was found between treatment response and G2677T/A or C3435T in ABCB1.
  
  
  CONCLUSIONS
  Our results indicate that among our pediatric patients with INS the C1236T polymorphism in the ABCB1 gene was associated with steroid resistance, while the A6986G polymorphism in the CYP3A5 gene showed a trend of association, but did not reach statistical significance, requiring further analysis.
authors.affiliation: Division of Pediatric Nephrology, Department of Pediatrics, Kaohsiung Veterans General Hospital, 386, Ta-Chung 1st Road, Zuoying District, Kaohsiung City, Taiwan. chysn@ms6.hinet.net
authors.forename: Yee-Hsuan
authors.initials: YH
authors.lastname: Chiou
authors.forename: Lin-Yu
authors.initials: LY
authors.lastname: Wang
authors.forename: Tzu-Hui
authors.initials: TH
authors.lastname: Wang
authors.forename: Shiao-ping
authors.initials: SP
authors.lastname: Huang
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D051544:Cytochrome P-450 CYP3A / Q000235:genetics*; D004351:Drug Resistance / Q000235:genetics*; D005260:Female; D005838:Genotype; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D009404:Nephrotic Syndrome / Q000188:drug therapy* / Q000235:genetics*; D011110:Polymorphism, Genetic; D011239:Prednisolone
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D005938:Glucocorticoids; D011239:Prednisolone; C510164:CYP3A5 protein, human; D051544:Cytochrome P-450 CYP3A