Glutathione S-transferase T1 (GSTT1) and M1 (GSTM1) polymorphisms in a sample of the population in Northern Italy

Glutathione S-transferase is a group of multifunctional enzymes important in the metabolism of xenobiotics. GSTT1 and GSTM1 are polymorphic in human populations. Since a relation between polymorphism and cancer susceptibility has been found, their distribution in human populations is of great interest. In the present study the distribution of GSTT1 and GSTM1 genotypes was studied in a total sample of 252 individuals of three localities of north-west Italy (Postua, Cavaglià and Biella) by PCR test. The frequencies of GSTT1 and GSTM1 "null" genotypes were respectively 7.94% and 34.92%. There are no significant differences between the populations studied in the GSTT1 "null" genotypes. On the other hand, for GSTM1 the frequency of gene deletion in Postua (25.5%) differs significantly (p < 0.01; chi-square test) from that of Biella (46.32%), which approaches the values indicated by most studies for Europeans (about 50%). The analysis of the frequencies of GSTT1 and GSTM1 polymorphisms among different age groups showed a lower frequency of negative genotypes in the older group, although not statistically confirmed.     

Polymorphisms of cytochrome P450 1A1, glutathione s-transferases M1 and T1 genes in Ouangolodougou (Northern Ivory Coast)

In this study, the frequencies of CYP1A1, GSTM1, and GSTT1 gene polymorphisms were determined in 133 healthy individuals from Ouangolodougou, a small rural town situated in the north of the Ivory Coast. As appeared in several published studies, ethnic differences in these frequencies have been found to play an important role in the metabolism of a relevant number of human carcinogens. In the studied sample, the frequencies of Ile/Ile (wild type), Ile/Val (heterozygous variant), and Val/Val (homozygous variant) CYP1A1 genotypes were 0.271, 0.692, and 0.037, respectively. Frequencies of GSTM1 and GSTT1 null genotypes were 0.361 and 0.331, respectively. No significant differences were noted between men and women. In contrast to published data for Africans, CYP1A1 *Val Allele frequency (0.383) was significantly high (p < 0.001) in this specific population. For the GSTT1 null genotype, no differences were found between the studied and other African populations, the contrary to what occurred for the GSTM1 null genotype in relation to Gambia and Egypt.     

Glutathione S-transferase M1 and T1 polymorphisms in Brazilian African descendants

The glutathione S-transferase gene family has an important role in the biotransformation and detoxification of different xenobiotics and endogenous compounds. Two polymorphic genes of this family, GSTM1 and GSTT1, present null alleles that consequently do not produce the respective enzyme when the genotype is homozygous. These polymorphisms are also interesting for population dynamics studies because they have great frequency variations among different ethnic groups and have been reported worldwide. The distribution of these alleles in urban and Amerindian populations in Brazil has been described, but none of those studies reported on African-descended rural populations. The aim of this study was to analyze the genotype frequency distribution of the GSTM1 and GSTT1 null alleles in an urban sample from the Federal District (n = 91) and in four semi-isolated African-descended populations: Mocambo (n = 55), Rio das R?s (n = 117), Riacho de Sacutiaba (n = 34), and Kalunga (n = 68). The GSTM1 and GSTT1 null genotype frequencies in these populations range from 17% to 35% for GSTM1 and from 22% to 44% for GSTT1. These values are similar to those described in other African and African-descended populations. Despite this range, there is no distribution difference among the analyzed populations. Combined GSTM1 and GSTT1 null genotype frequencies range from 6% to 13% and are similar to European-derived populations, suggesting admixture with this ethnic group. This can be interpreted as a European contribution to these African-descended populations. Regarding the urban population in the Federal District, our results suggest an important African and European contribution.     

GSTT1 and GSTM1 gene polymorphisms in European and African populations

Glutathione S-transferases (GSTs) are a superfamily of detoxificant enzymes. Pharmacogenomic studies have revealed interethnic differences in GST allelic frequencies. This study is focused on GSTT1 (gene deletion, rs17850155, rs2234953, and rs11550605) and GSTM1 (gene deletion) gene frequency distributions in two population samples of Europe origin (Italy, n = 120; Spain, n = 94) and two population samples of Africa origin (Cameroon, n = 126; Ethiopia, n = 153). Detection of GSTT1 and GSTM1 null genotypes was performed by multiplex PCR analysis, while the other GSTT1 gene polymorphisms were detected using allele specific PCR and sequencing. GSTT1 and GSTM1 null frequencies in the samples analyzed fit with the variability range observed in European and African populations, respectively. The SNP analysis in GSTT1 gene did not highlight any nucleotide substitution in 493 individuals analyzed. The comparisons among GSTM1 and GSTT1 null phenotype frequencies in worldwide populations show different patterns between Asians, Africans, and Europeans. Important insights into the effects of GSTM1 and GSTT1 gene deletions on the pathogenesis of human diseases have been hypothesized. Detailed studies on the geography of GST variants could therefore increase knowledge about the relationship between ethnicity and the prevalence of certain diseases.     

Genetic polymorphisms of glutathione S-transferase T1 (GSTT1) and M1 (GSTM1) in selected populations of Afghanistan

Genetic polymorphisms in genes encoding glutathione S-transferase T1 (GSTT1, a member of class theta) and M1 (GSTM1, a member of class mu) have been defined. Previous studies have revealed that there was significant difference between populations for allelic frequency of several members of GSTs. In order to find the prevalence of null genotypes of GSTM1 and GSTT1 in Afghanis populations the present study was carried out. The total study subjects consisted of 656 unrelated healthy Afghanis refugees living in Fars province (southern Iran). From these 257, 217, 120, and 62 individuals were Pashtuns, Tajiks, Hazaras, and Uzbeks, respectively. Genetic polymorphisms for GSTT1 and GSTM1 were detected by multiplex PCR. The prevalence of null genotype of GSTM1 in Pashtuns, Tajiks, Hazaras, and Uzbeks was 42.4, 48.4, 52.5, and 40.3 %, respectively. There was no significant difference between these populations for the genotypic distribution of the GSTM1 polymorphism (χ(2) = 4.67, df = 3, P = 0.197). The frequency of GSTT1 null genotype in Pashtuns, Tajiks, Hazaras, and Uzbeks was 7.4, 25.3, 25.0, and 29.0 %, respectively. The observed difference between populations for prevalence of GSTT1 null genotype was statistically significant (χ(2) = 35.54, df = 3, P < 0.001). In comparison with European and Asian populations, Afghanistan populations like Iranian populations showed intermediate frequency for GSTT1 and GSTM1 null genotypes.     

Combined genotype analysis of GSTM1 and GSTT1 polymorphisms in a Polish population

This study describes the distribution of GSTT1 and GSTM1 polymorphisms in a normal population of central Poland. A homozygous inherited deletion of either gene leads to absence of enzyme activity in affected individuals, and those lacking more than one detoxifying gene are at the highest risk for diseases caused by environmental factors. The prevalence of the "null" genotype of the GSTM1 and GSTT1 genes was determined by using a multiplex polymerase chain reaction methodology in a group of 233 healthy individuals. We found the following frequencies of individuals with mutated alleles: 47.6% were homozygously deficient for GSTM1 (51.1% males, 42.4% females) and 16.3% for GSTT1 (17.7% males, 15.2% females). The combined analyses GSTM1/GSTT1 revealed the following genotypes: +/+, 44.2% (42.6% males, 46.7% females); "null"/+, 39.1% (39.7% males, 38.0% females); +/"null," 8.6% (7.1% males, 10.9% females); "null"/"null," 8.1% (10.6% males, 4.4% females). Of interest is the small number of women lacking both genes. Significant differences occurred between men and women in some age groups, which could suggest that sex differences in susceptibility to diseases may be caused by genotype differences in detoxifying enzymes such as glutathione S-transferase. The data obtained may prove to be useful for epidemiological studies.     

Genotype frequencies of polymorphic GSTM1, GSTT1, and cytochrome P450 CYP1A1 in Mexicans

The genotype frequencies of three metabolic polymorphisms were determined in a sample of a typical community in central Mexico. CYP1A1*3, GSTM1, and GSTT1 polymorphisms were studied in 150 donors born in Mexico and with Mexican ascendants; with respect to ethnicity the subjects can be considered Mestizos. PCR reactions were used to amplify specific fragments of the selected genes from genomic DNA. An unexpected 56.7% frequency of the CYP1A1*3 allele (which depends on the presence of a Val residue in the 462 position of the enzyme, instead of Ile) was found, the highest described for open populations of different ethnic origins (i.e., Caucasian, Asian, African, or African American). The GSTM1 null genotype was found with a frequency of 42.6%, which is not different from other ethnicities, whereas the GSTT1 null genotype had a frequency of 9.3%, one of the lowest described for any ethnic group but comparable to the frequency found in India (9.7%). The frequency of the combined genotype CYP1A1*3/*3 and the GSTM1 null allele is one of the highest observed to date (or perhaps the highest): 13.7% among all the ethnicities studied, including Caucasians and Asians, whereas the combination of CYP1A1*3/*3 with the GSTT1 null allele reached only 2.8%. The GSTM1 null allele combined with the GSTT1 null allele, on the other hand, has one of the lowest frequencies described, 4.24%, comparable to the frequencies found in African Americans and Indians. Finally, the combined CYP1A1*3/*3, GSTM1 null allele, and GSTT1 null allele genotype could not be found in the sample studied; it is assumed that the frequency of carriers of these combined genotypes is less than 1%. CYP1A1*3 and CYP1A1*2 polymorphisms were also evaluated in 50 residents in a community of northern Mexico; the CYP1A1*3 frequency was 54%, similar to that found in the other community studied, and the CYP1A1*2 frequency was 40%, which is high compared to Caucasians and Asians but comparable to the frequency found in Japanese and lower than the frequency found in Mapuche Indians. Haplotype frequencies for these CYP1A1 polymorphisms were estimated, and a linkage disequilibrium value (D) of 0.137 was calculated.     

Investigation of glutathione S-transferase M1 and T1 deletions in lung cancer

Glutathione S-transferases (GSTs) M1 and T1 are known to be polymorphic in humans. Both polymorphisms are due to gene deletions which are responsible for the existence of null genotypes. Previous studies have suggested that GST genotypes may play a role in determining susceptibility to a number of unrelated cancers, including lung cancer. The GSTM1 and GSTT1 polymorphisms were determined by PCR-based analysis in 75 lung cancer patients and 55 controls. The unconditional logistic regression analysis was used to calculate ORs and 95% CI. The frequencies of GSTM1 and GSTT1 null genotypes were 37.3 and 22.7% in lung cancer patients and 27.3 and 16.4% in controls, respectively. When analyzed by histology the GSTM1 null genotype was more prevalent in squamous-cell carcinoma and adenocarcinoma patients. Whereas, GSTT1 null genotype frequency was lower in small-cell lung cancer patients than controls. But these differences were not statistically significant. According to smoking status, null genotype for both gene are associated with an increase in risk for lung cancer. Our results suggest that GSTM1 and GSTT1 polymorphisms may play a role in the development of lung cancer for some histological subtypes and modifies the risk of smoking-related lung cancer.     

Females with paired occurrence of cancers in the UADT and genital region have a higher frequency of either Glutathione S-transferase M1/T1 null genotype

Upper Aero digestive Tract (UADT) is the commonest site for the development of second cancer in females after primary cervical cancer. Glutathione S-transferase (GSTM1 and / or T1) null genotype modulates the risk of developing UADT cancer (primary as well as second cancer). The aim of this study was to evaluate the difference in GST null genotype frequencies in females with paired cancers in the UADT and genital region as compared to females with paired cancers in the UADT and non-genital region. Forty-nine females with a cancer in the UADT and another cancer (at all sites-genital and non-genital) were identified from a database of patients with multiple primary neoplasms and were analyzed for the GSTM1 and T1 genotype in addition to known factors such as age, tobacco habits, alcohol habits and family history of cancer. Frequencies of GSTM1 null, GSTT1 null, and either GSTM1/T1 null were higher in females with paired occurrence of cancer in the UADT and genital site (54%, 33% and 75% respectively) in comparison to females with paired occurrence of cancer in the UADT and non-genital sites (22%, 6% and 24% respectively). The significantly higher inherited frequency of either GSTM1/T1 null genotype in females with a paired occurrence of cancers in UADT and genital region (p = 0.01), suggests that these females are more susceptible to damage by carcinogens as compared to females who have UADT cancers in association with cancers at non-genital sites.     

Frequencies of GSTM1, GSTT1, and GSTP1 polymorphisms in a Brazilian population

The glutathione S-transferase (GST) family of enzymes has a vital role in phase II of biotransformation of environmental carcinogens, pollutants, drugs and other xenobiotics. GSTs are polymorphic, with the type and frequency of polymorphism being ethnic dependent. Polymorphisms in GST genes have been shown to be associated with susceptibility to disease and disease outcome. We determined the frequencies of GSTM1, GSTT1 and GSTP1 polymorphisms in 591 volunteers who had been residents of Rio de Janeiro for at least six months. Blood was collected and DNA extracted by proteinase K/SDS digestion. Information about social habits and health problems was also recorded. GSTM1 and GSTT1 polymorphisms were analyzed by a PCR-Multiplex procedure, whereas GSTP1 polymorphism was analyzed by PCR-RFLP. We found that 42.1% (48.9% of whites and 34.2% of non-whites) of the individuals had the GSTM1 null genotype, whereas 25.4% (25.1% of whites and 25.7% of non-whites) had the GSTT1 null genotype. The genotypic distribution of GSTP1 was 49.7% I/I, 38.1% I/V, and 12.2% V/V, whereas the allelic frequencies were 0.69 for the Ile allele, and 0.31 for the Val allele. The frequencies of GST polymorphisms in this Brazilian population were found to be different from those observed in other populations, particularly of other South American countries.     

Polymorphism of glutathione S-transferases M1 and T1 in several populations of Russia

Frequencies of the wild-type and null genotypes of the GSTM1 and GSTT1 genes were established in healthy donors from several Russian populations (ethnic Russians from the towns of Oshevensk and Kholmogory, Arkhangel'sk oblast; ethnic Khants; ethnic Kalmyks; and ethnic Buryats) in order to identify the ethnic group with the maximal frequency of the null genotype. The highest frequency of individuals with the null genotype of both genes was observed in the Kalmyk and Buryat populations. The results may be used to study the effect of climatic and ecological conditions on multifactorial disease incidence in populations.     

Glutathione S-transferase mu 1 (GSTM1) and theta 1 (GSTT1) genetic polymorphisms and atopic asthma in children from Southeastern Brazil

Xenobiotics can trigger degranulation of eosinophils and mast cells. In this process, the cells release several substances leading to bronchial hyperactivity, the main feature of atopic asthma (AA). GSTM1 and GSTT1 genes encode enzymes involved in the inactivation of these compounds. Both genes are polymorphic in humans and have a null variant genotype in which both the gene and corresponding enzyme are absent. An increased risk for disease in individuals with the null GST genotypes is therefore, but this issue is controversial. The aim of this study was to investigate the influence of the GSTM1 and GSTT1 genotypes on the occurrence of AA, as well as on its clinical manifestations. Genomic DNA from 86 patients and 258 controls was analyzed by polymerase chain reaction. The frequency of the GSTM1 null genotype in patients was higher than that found in controls (60.5% versus 40.3%, p = 0.002). In individuals with the GSTM1 null genotype the risk of manifested AA was 2.3-fold higher (95%CI: 1.4-3.7) than for others. In contrast, similar frequencies of GSTT1 null and combined GSTM1 plus GSTT1 null genotypes were seen in both groups. No differences in genotype frequencies were perceived in patients stratified by age, gender, ethnic origin, and severity of the disease. These results suggest that the inherited absence of the GSTM1 metabolic pathway may alter the risk of AA in southeastern Brazilian children, although this must be confirmed by further studies with a larger cohort of patients and age-matched controls from the distinct regions of the country.     

Trimodal GSTT1 and GSTM1 genotyping assay by real-time PCR

The GSTT1 and GSTM1 genes are characterized by the existence of a GST*0 null allele responsible for a lack of enzyme activity, with the respective null genotypes GSTT1*0/0 and GSTM1*0/0. The three resulting genotypes (GSTs*1/1, *1/0 and *0/0) are associated with a trimodal distribution of glutathione-conjugator activity. Previous epidemiological studies have only evaluated the cancer risk associated with the GST null genotype relative to the two GST carrier genotypes (GSTs1*1/1 and *1/0). We developed GSTT1 and GSTM1 TaqMan real-time quantitative PCR assays to discriminate each of the three genotypes, with the albumin gene (ALB) as reference. The mean N(GSTT1*1/1) value was 1.0 (95% confidence interval 0.80-1.20). The mean N(GSTT1*1/0) value was 0.48 (95% CI 0.36-0.60). One (3.4%) of the 29 DNA samples yielded the GSTM1*1/1 genotype (N(GSTM1*1/1) = 1), a frequency in keeping with the Hardy-Weinberg distribution. The mean N(GSTM1*1/0) value was 0.50 (95% CI 0.42-0.58). All GSTT1*0/0 and GSTM1*0/0 samples yielded N(GST) values of 0 (Ct = 40); the frequencies of these genotypes (27.6% and 55.2%, respectively) were in keeping with published data. The GSTT1 and GSTM1 real-time PCR assays described here unambiguously discriminate each of the three existing genotypes which should be valuable for assessing the relative risk of cancer associated with each of the three GST genotypes.     

Glutathione-S-transferase M1 and T1 genes and gastric cancer: a case control study in North Indian population

Background

Difference in the capacity of xenobiotic metabolising enzymes might be an important factor in genetic susceptibility to cancer.

Methods

A case control study involving forty one gastric cancer patients and one hundred and thirty controls was carried out to determine the frequency of GSTM1 and GSTT1 null genotypes. The frequency of GSTM1 and GSTT1 null genotype was observed by carrying out multiplex PCR.

Results

There was no difference in the frequencies of the GSTM1 and GSTT1 null and the combined GSTM1 and GSTT1 null genotype between patients and control.

Conclusions

Our data suggest that GSTM1 and GSTT1 status may not influence the risk of developing gastric cancer.     

Polymorphism of Glutathione S-Transferases M1 and T1 in Several Populations of Russia

Frequencies of the wild-type and null genotypes of the GSTM1 and GSTT1 genes were established in healthy donors from several Russian populations (ethnic Russians from the towns of Oshevensk and Kholmogory, Arkhangel'sk oblast; ethnic Khants; ethnic Kalmyks; and ethnic Buryats) in order to identify the ethnic group with the maximal frequency of the null genotype. The highest frequency of individuals with the null genotype of both genes was observed in the Kalmyk and Buryat populations. The results may be used to study the effect of climatic and ecological conditions on multifactorial disease incidence in populations.     

The role of GSTM1, GSTT1, GSTP1, and OGG1 polymorphisms in type 2 diabetes mellitus risk: a case-control study in a Turkish population

The aim of the present study was to investigate the role of some polymorphisms in GSTs (GSTM1, GSTT1 and GSTP1) which are very important protective mechanisms against oxidative stress and in OGG1 gene which is important in DNA repair, against the risk of type 2 diabetes mellitus (T2DM). 127 T2DM and 127 control subjects were included in the study. DNA was extracted from whole blood. Analyses of GSTM1 and GSTT1 gene polymorphisms were performed by allele specific PCR and those of GSTP1 Ile105Val and OGG1 Ser326Cys by PCR-RFLP. Our data showed that GSTM1 null genotype frequency had a 2-6 times statistically significant increase in a patient group (OR=3.841, 95% CI=2.280-6.469, p<0.001) but no significance with GSTT1 null/positive and GSTP1 Ile105Val genotypes was observed. When T2DM patients with OGG1 Ser326Cys polymorphism were compared with patients with a wild genotype, a 2-3 times statistically significant increase has been observed (OR 1.858, 95% CI=1.099-3.141, p=0.021). The combined effect of GSTM1 null and OGG1 variant genotype frequencies has shown to be statistically significant. Similarly, the risk of T2DM was statistically increased with GSTM1 null (OR=3.841, 95% CI=2.28-6.469), GSTT1 null+GSTP1 (H+M) (OR=4.118, 95% CI=1.327-12.778) and GSTM1 null+OGG1 (H+M) (OR=3.322, 95% CI=1.898-5.816) and GSTT1 null+OGG1 (H+M) (OR=2.179, 95% CI=1.083-4.386) as compared to the control group. According to our study results, it has been observed that the combined evaluation of GSTM1-GSTT1-GSTP1 and OGG1 Ser326Cys gene polymorphisms can be used as candidate genes in the etiology of T2DM, especially in the development of T2DM.     

No contribution of GSTM1 and GSTT1 null genotypes to the risk of neutropenia due to benzene exposure in Southeastern Brazil

Exposure to benzene has been associated with haematological diseases such as neutropenia (NEB) and acute myeloid leukaemia (AML). We tested whether the null genotypes of the GSTM1 and GSTT1 genes, involved in benzene inactivation, altered the risk for NEB in southeastern Brazil. Genomic DNA from 55 NEB patients and 330 controls was analysed by multiplex-polymerase chain reaction. The frequency of the GSTM1, GSTT1 and combined null genotypes was similar in patients and controls (GSTM1, 27.3% vs. 38.8%, p = 0.16; GSTT1, 25.5% vs. 19.7%, p = 0.24; GSTM1/GSTT1, 12.7% vs. 6.7%, p = 0.26; respectively). The distribution of genotype classes in NEB patients was similar to normal controls, suggesting that GSTM1 and GSTT1 null genotypes make no specific contribution to the risk of NEB. As the GSTM1 and GSTT1 null genotypes were previously associated with increased risk for AML in Brazil and elsewhere, we hypothesise that different thresholds of chemical exposure relative to distinct GSTM1 and GSTT1 genotypes may determine whether AML or NEB manifests in benzene exposed individuals from southeastern Brazil. Although indicative, our results still require support by prospective and large scale epidemiological studies, with rigorous assessment of daily chemical exposures and control of the possible contribution of other polymorphic genes involved in benzene metabolism.     

Glutathione <Emphasis Type="BoldItalic">S</Emphasis>-transferase M1 and T1 null genotype frequency distribution among four tribal populations of western India

Glutathione S-transferase (GST) family is a key contributor in the detoxification mechanism of our body. Deletion of the genes within this family has been reported in the failure of detoxification system, to some extent leading to various types of cancers and other life threatening diseases. The existing data and reports on the association of null genotype of both GSTM1 and GSTT1 genes for various diseases are inconsistent. But knowledge of the polymorphic distributions of genotypes in different populations is important for investigating the risk factors in different epidemiological studies. The present study thus aims to determine the frequency of GSTM1 and GSTT1 null genotype frequency among four tribal groups, i.e. Mina, Garasia, Damor and Saharia of western India. A comparative analysis with different tribal as well as world population has also been undertaken to have a view of its worldwide frequency distribution. Our results reveal a frequency distribution varying from 22.6% to 66.9% with respect to GSTM1 gene polymorphism and from 19.1% to 33.0% with respect to GSTT1 gene in the studied populations. To the best of our knowledge this is the first report on the GSTM1 and GSTT1 frequency distribution among the tribal population of western India and our study shows that the Mina tribal population has the highest frequency of GSTM1.     

Glutathione S-transferase T1 (GSTT1) and M1 (GSTM1) polymorphisms in a sample of the population in Northern Italy

Glutathione S-transferase is a group of multifunctional enzymes important in the metabolism of xenobiotics. GSTT1 and GSTM1 are polymorphic in human populations. Since a relation between polymorphism and cancer susceptibility has been found, their distribution in human populations is of great interest. In the present study the distribution of GSTT1 and GSTM1 genotypes was studied in a total sample of 252 individuals of three localities of northwest Italy (Postua, Cavaglià, and Biella) by PCR test. The frequencies of GSTT1 and GSTM1 “null” genotypes were respectively 7.94 and 34.92%. There are no significant differences between the populations studied in the GSTT1 “null” genotypes. On the other hand, for GSTM1 the frequency of gene deletion in Postua (25.5%) differs significantly (P < 0.01; χ² test) from that of Biella (46.32%), which on the other hand approaches the values indicated by most studies for Europeans (about 50%). The analysis of the frequencies of GSTT1 and GSTM1 polymorphisms among different age groups showed a lower frequency of negative genotypes in the older group, although not statistically confirmed. The text was submitted by the authors in English.     

Association of glutathione S-transferase gene polymorphisms (GSTM1 and GSTT1) of vitiligo in Korean population

Vitiligo is an acquired pigmentary disorder of the skin involving melanocyte dysfunction. It has been reported that melanocyte impairment could be related to increased oxidative stress. The glutathione S-transferases (GSTs) are group of polymorphic enzymes that are important in protection against oxidative stress. To find the relationship between GSTM1 and GSTT1 polymorphisms with vitiligo susceptibility, GSTM1 and GSTT1 (homozygous deletion vs. non-deleted) polymorphisms between vitiligo patients (n=310) and healthy controls (n=549) were analyzed. We observed significant association in null alleles of the GSTM1 (P<0.001, OR=2.048, 95% CI=1.529-2.743). GSTM1 null type was also statistically different between two vitiligo subtypes and controls (Focal P<0.001, OR=2.224, 95% CI=1.499-3.298; Generalized P=0.001, OR=1.974, 95% CI=1.342-2.904). However, no significant association in GSTT1 (P=0.869, OR=1.024, 95% CI=0.775-1.353) was observed with vitiligo. In combined analysis of GSTM1 and GSTT1, both null type and GSTM1/GSTT1 (null/present) group showed significant differences between controls and vitiligo patients. These results suggest that GSTM1 null type might be associated with vitiligo susceptibility in Korean population.