title: Influence of A-21T and C-262T genetic polymorphisms at the promoter region of the catalase (CAT) on gene expression.
abstract: OBJECTIVE
  Catalase (CAT, OMIM: 115500) is one of the major antioxidant enzymes, which plays an important role in the clearance of reactive oxygen species. Three genetic polymorphisms of A-21T (rs7943316), C-262T (rs1001179), and C-844T (rs769214) in the promoter region of the CAT have been reported. It has been suggested that these polymorphisms may alter the recognition sites of transcriptional factors, therefore it might be concluded that these polymorphisms may alter the expression levels of the gene. The aim of the present study is to evaluate the associations between these genetic variations and the CAT mRNA levels in human peripheral blood cells.
  
  
  METHODS
  The present study consisted of 47 healthy students of Shiraz University (south-west Iran). Genotypes of the CAT polymorphisms were determined by PCR based method. The quantitative CAT mRNA expression levels were investigated using quantitative real-time PCR.
  
  
  RESULTS
  Analysis of variance revealed significant differences between the study genotypes (For A-21T polymorphism: F = 7.45; df = 2, 44; P = 0.002; For C-262T polymorphism: F = 15.17; df = 2, 44; P < 0.001). The studied polymorphisms showed linkage disequilibrium (D' = 1.0, r2= 0.1813, χ2= 17.03, P < 0.0001). The mRNA levels of CAT in the AC/TT, TC/TC, TC/TT, and TC/TC diplotypes significantly were higher than the mRNA levels in AC/AC diplotype. There was a significant difference between the study genotypes (F = 9.24; df = 5, 41; P < 0.001). The TC/TC and TT/TT diplotypes showed about 2 and 4 folds CAT mRNA levels compared with the AC/AC diplotype.
  
  
  CONCLUSIONS
  The present findings indicated that these polymorphisms were significantly associated with the gene expression.
authors.affiliation: Department of Biology, College of Sciences, Shiraz University, Shiraz, 71467-13565, Iran.
authors.forename: Khyber
authors.initials: K
authors.lastname: Saify
authors.affiliation: Department of Biology, College of Sciences, Shiraz University, Shiraz, 71467-13565, Iran.
authors.forename: Iraj
authors.initials: I
authors.lastname: Saadat
authors.affiliation: Department of Biology, College of Sciences, Shiraz University, Shiraz, 71467-13565, Iran. saadat@shirazu.ac.ir.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Saadat
mesh_terms: D000328:Adult; D002374:Catalase / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D007492:Iran; D008297:Male; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013334:Students; D014495:Universities; D055815:Young Adult
chemical_list: D012333:RNA, Messenger; C577219:CAT protein, human; D002374:Catalase
keywords: CAT; Polymorphism; mRNA level