Genetic polymorphism of GSTT1 may be under natural selection in a population chronically exposed to natural sour gas.
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.
Zendeh-Boodi
Zahra
Z
Department of Biology, College of Sciences, Shiraz University, Shiraz, 71454, Iran.
Saadat
Mostafa
M
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
D005579:Fossil Fuels; D005982:Glutathione Transferase; D013457:Sulfur Compounds; C413545:glutathione S-transferase T1