title: Cytochrome P450 (CYP3A4*18) and glutathione-S-transferase (GSTP1) polymorphisms in a healthy Tunisian population.
abstract: OBJECTIVE
  Human cytochrome P450 3A and glutathione S-transferase (GST) enzymes evolved to catalyze the metabolism of numerous common therapy drugs and endogenous molecules. Members of the CYP3A are the majority expressed in human liver and intestine. The genetic factors play an important role in the interindividual variability in CYP3A and GST activity. Detection of CYP3A4 and GST variant alleles and knowledge about their allelic frequency in specific ethnic groups are important to lead to individualized drug dosing and improved therapeutics.
  
  
  METHODS
  We determined the allelic frequency of the CYP3A4*18 and GSTP1 in a group of 138 healthy Tunisian subjects using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays. It is based on a specific PCR product cut by restriction endonucleases. This method offers the advantage of cutting DNA by the appropriate restriction enzyme at the correct mutation site hence enhancing its reliability. Electrophoretic separation demonstrates the presence (or absence) of restriction sites.
  
  
  RESULTS
  In the group of 138 unrelated individuals, the frequencies of the CYP3A4*18 and GSTP1 variant allele in this Tunisian population were 0.02 and 0.01, respectively.
  
  
  CONCLUSIONS
  The present study describes polymorphisms of Cyp3A4 and GST among Tunisian subjects. We developed a simple assay for the detection of the CYP3A4*18 and GSTP1 polymorphisms and we compared our allelic frequencies to other populations. No significant difference was obtained. This study provides the first analysis of CYP3A4*18 and GSTP1 mutant allele frequencies in the Tunisian population.
authors.affiliation: Laboratory for Research on Biologically Compatible Compounds (LRSBC), Monastir, Tunisia.
authors.forename: Chiraz
authors.initials: C
authors.lastname: Zaied
authors.forename: Salwa
authors.initials: S
authors.lastname: Abid
authors.forename: Nabil
authors.initials: N
authors.lastname: Mtiraoui
authors.forename: Dorsaf
authors.initials: D
authors.lastname: Zellema
authors.forename: Abdelthif
authors.initials: A
authors.lastname: Achour
authors.forename: Hassan
authors.initials: H
authors.lastname: Bacha
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D044383:Black People / Q000235:genetics*; D051544:Cytochrome P-450 CYP3A / Q000235:genetics*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D051549:Glutathione S-Transferase pi / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D014416:Tunisia; D055815:Young Adult
chemical_list: D003577:Cytochrome P-450 Enzyme System; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human; D051549:Glutathione S-Transferase pi