Distribution of GSTM1 and GSTT1 polymorphisms among caucasians and the three major ethnic groups in Malaysia

Glutathione S-transferases (GSTs) are the vital Phase II enzymes to detoxify carcinogens and reactive oxygen species in the body, which encoded by GST mu class 1 (GSTM1) and GST theta class 1 (GSTT1) genes. Polymorphism in the genes affects the enzyme expression and increases the susceptibility to d...

Full description

Saved in:
Bibliographic Details
Main Author: Wan Rashidi, Wan Nooremira
Format: Thesis
Language:English
Published: 2018
Subjects:
Online Access:http://psasir.upm.edu.my/id/eprint/76283/1/FPSK%28M%29%202018%2018%20-%20IR.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-upm-ir.76283
record_format uketd_dc
spelling my-upm-ir.762832019-11-28T10:58:42Z Distribution of GSTM1 and GSTT1 polymorphisms among caucasians and the three major ethnic groups in Malaysia 2018-04 Wan Rashidi, Wan Nooremira Glutathione S-transferases (GSTs) are the vital Phase II enzymes to detoxify carcinogens and reactive oxygen species in the body, which encoded by GST mu class 1 (GSTM1) and GST theta class 1 (GSTT1) genes. Polymorphism in the genes affects the enzyme expression and increases the susceptibility to disease. GSTM1 and GSTT1 deletions present in 50% and 20% of Caucasian population, 54% and 37% in Africans, and 62% and 20% in Asians, respectively, showing ethnicdependent polymorphism of both genes. However, the genetic polymorphisms are less reported in Malaysia predominantly between three major ethnics; Malay, Indian and Chinese. In addition, the rate of GST polymorphisms in Malaysia has not been precisely compared with Caucasian population using the standard genome reference, European Collection of Cell Culture (ECACC). Therefore, this research was to determine the distribution of GSTM1 and GSTT1 polymorphisms among three different ethnic groups in Malaysia and Caucasians. One to three milliliters of peripheral blood were collected from 518 individuals comprised of 262 Malays, 151 Chinese and 105 Indians. DNA was extracted using QIAamp DNA blood mini kit and quantified using NanoDrop™ Lite Spectrophotometry. Meanwhile, 192 DNA samples (ECACC HRC-1 and HRC-2) were commercially bought to represent Caucasians group. All DNA samples proceed with multiplex PCR to determine GSTM1 and GSTT1 deletion simultaneously in the presence of internal control, Albumin (ALB) gene. The genotypes were then validated using DNA sequencing. Chi Square test was carried out to compare the genotype frequencies among three Malaysian ethnic groups and between the whole study cohort in Malaysia and Caucasians at p<0.05 as significant difference level. This study recorded three categories of genotypes; GSTM1 null, GSTT1 null, and combined GSTM1 and GSTT1 null. There was a significant difference between the three Malaysian ethnic groups in all genotype categories (p<0.001). GSTM1 null was found in 62.2% of Malays, 48.3% of Chinese and 29.5% of Indians. As for GSTT1, the null frequency was higher among Chinese (47.7%) followed by Malays (39.7%), and lowest in Indians (9.5%) respondents. Meanwhile, the combined null genotypes were recorded in 26.0% of Malay, 21.2% of Chinese, and 2.9% of Indian. In overall, the whole study cohort in Malaysia and Caucasians were significantly different in the null genotype of GSTT1 and combined genes (p<0.001). Malaysia has a higher null frequency of 35.9% for GSTT1 and 19.9% for combined genes than Caucasians (16.7% for GSTT1 and 8.9% for combined genes). The distributions of GSTM1 in Malaysia are similar to those reported among Africans, Caucasians and Asians whereas the frequency of GSTT1 null varies among those populations. In conclusion, Malaysia has a high rate of GSTM1 and GSTT1 null genotypes, and Malays showed the highest frequency among the three major ethnics. This study provides further evidence for ethnic variation in metabolism and disposition, and these genotype data will help future genetic studies on the GST polymorphisms in association with disease risks and drug effects in Malaysia. Glutathione Transferase Structure - Activity Relationship 2018-04 Thesis http://psasir.upm.edu.my/id/eprint/76283/ http://psasir.upm.edu.my/id/eprint/76283/1/FPSK%28M%29%202018%2018%20-%20IR.pdf text en public masters Universiti Putra Malaysia Glutathione Transferase Structure - Activity Relationship
institution Universiti Putra Malaysia
collection PSAS Institutional Repository
language English
topic Glutathione Transferase
Structure - Activity Relationship

spellingShingle Glutathione Transferase
Structure - Activity Relationship

Wan Rashidi, Wan Nooremira
Distribution of GSTM1 and GSTT1 polymorphisms among caucasians and the three major ethnic groups in Malaysia
description Glutathione S-transferases (GSTs) are the vital Phase II enzymes to detoxify carcinogens and reactive oxygen species in the body, which encoded by GST mu class 1 (GSTM1) and GST theta class 1 (GSTT1) genes. Polymorphism in the genes affects the enzyme expression and increases the susceptibility to disease. GSTM1 and GSTT1 deletions present in 50% and 20% of Caucasian population, 54% and 37% in Africans, and 62% and 20% in Asians, respectively, showing ethnicdependent polymorphism of both genes. However, the genetic polymorphisms are less reported in Malaysia predominantly between three major ethnics; Malay, Indian and Chinese. In addition, the rate of GST polymorphisms in Malaysia has not been precisely compared with Caucasian population using the standard genome reference, European Collection of Cell Culture (ECACC). Therefore, this research was to determine the distribution of GSTM1 and GSTT1 polymorphisms among three different ethnic groups in Malaysia and Caucasians. One to three milliliters of peripheral blood were collected from 518 individuals comprised of 262 Malays, 151 Chinese and 105 Indians. DNA was extracted using QIAamp DNA blood mini kit and quantified using NanoDrop™ Lite Spectrophotometry. Meanwhile, 192 DNA samples (ECACC HRC-1 and HRC-2) were commercially bought to represent Caucasians group. All DNA samples proceed with multiplex PCR to determine GSTM1 and GSTT1 deletion simultaneously in the presence of internal control, Albumin (ALB) gene. The genotypes were then validated using DNA sequencing. Chi Square test was carried out to compare the genotype frequencies among three Malaysian ethnic groups and between the whole study cohort in Malaysia and Caucasians at p<0.05 as significant difference level. This study recorded three categories of genotypes; GSTM1 null, GSTT1 null, and combined GSTM1 and GSTT1 null. There was a significant difference between the three Malaysian ethnic groups in all genotype categories (p<0.001). GSTM1 null was found in 62.2% of Malays, 48.3% of Chinese and 29.5% of Indians. As for GSTT1, the null frequency was higher among Chinese (47.7%) followed by Malays (39.7%), and lowest in Indians (9.5%) respondents. Meanwhile, the combined null genotypes were recorded in 26.0% of Malay, 21.2% of Chinese, and 2.9% of Indian. In overall, the whole study cohort in Malaysia and Caucasians were significantly different in the null genotype of GSTT1 and combined genes (p<0.001). Malaysia has a higher null frequency of 35.9% for GSTT1 and 19.9% for combined genes than Caucasians (16.7% for GSTT1 and 8.9% for combined genes). The distributions of GSTM1 in Malaysia are similar to those reported among Africans, Caucasians and Asians whereas the frequency of GSTT1 null varies among those populations. In conclusion, Malaysia has a high rate of GSTM1 and GSTT1 null genotypes, and Malays showed the highest frequency among the three major ethnics. This study provides further evidence for ethnic variation in metabolism and disposition, and these genotype data will help future genetic studies on the GST polymorphisms in association with disease risks and drug effects in Malaysia.
format Thesis
qualification_level Master's degree
author Wan Rashidi, Wan Nooremira
author_facet Wan Rashidi, Wan Nooremira
author_sort Wan Rashidi, Wan Nooremira
title Distribution of GSTM1 and GSTT1 polymorphisms among caucasians and the three major ethnic groups in Malaysia
title_short Distribution of GSTM1 and GSTT1 polymorphisms among caucasians and the three major ethnic groups in Malaysia
title_full Distribution of GSTM1 and GSTT1 polymorphisms among caucasians and the three major ethnic groups in Malaysia
title_fullStr Distribution of GSTM1 and GSTT1 polymorphisms among caucasians and the three major ethnic groups in Malaysia
title_full_unstemmed Distribution of GSTM1 and GSTT1 polymorphisms among caucasians and the three major ethnic groups in Malaysia
title_sort distribution of gstm1 and gstt1 polymorphisms among caucasians and the three major ethnic groups in malaysia
granting_institution Universiti Putra Malaysia
publishDate 2018
url http://psasir.upm.edu.my/id/eprint/76283/1/FPSK%28M%29%202018%2018%20-%20IR.pdf
_version_ 1747813148169076736