title: Genetic polymorphism of GSTT1 may be under natural selection in a population chronically exposed to natural sour gas.
abstract: OBJECTIVE
  In order to examine whether chronic exposure to natural sour gas containing sulfur compounds act as natural selection force on genetic polymorphisms of glutathione S-transferase M1 (GSTM1) and T1 (GSTT1), the present study was done.
  
  
  METHODS
  The study was performed on two groups of healthy individuals of Masjid-i-Sulaiman (Khozestan province, southwest of Iran) citizens with the mean ages of 47.5 +/- 12.4 (36 male and 58 female) and 16.3 +/- 2.4 (47 male and 140 female) that were considered as first and second generation, respectively. The GSTT1 and GSTM1 genotypes were determined using a PCR-based method.
  
  
  RESULTS
  The genotypic frequencies of GSTM1 did not change significantly (chi(2) = 0.085, df = 1, P = 0.770). The frequency of the GSTT1 null genotype was 52.1% in the first generation and reached to 36.4% in the second generation. There was significant difference between two generations for the GSTT1 polymorphism (chi(2) = 6.397, df = 1, P = 0.011).
  
  
  CONCLUSIONS
  It was suggested that the GSTT1 polymorphism may be under natural selection because of probably favored ability of GSTT1-active genotype to survival and reproduction.
authors.affiliation: Department of Biology, College of Sciences, Shiraz University, Shiraz, 71454, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Zendeh-Boodi
authors.forename: Mostafa
authors.initials: M
authors.lastname: Saadat
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005579:Fossil Fuels / Q000633:toxicity*; D020022:Genetic Predisposition to Disease; D005828:Genetics, Population; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D007492:Iran; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D044382:Population Groups / Q000235:genetics; D012641:Selection, Genetic; D013457:Sulfur Compounds / Q000633:toxicity
chemical_list: D005579:Fossil Fuels; D005982:Glutathione Transferase; D013457:Sulfur Compounds; C413545:glutathione S-transferase T1