Frequency of glutathione-S-transferase null-M1 and null-T1 genotypes among the Turabah population in Saudi Arabia

Abstract

ABSTRACT. Glutathione-S-transferases (GST) are key phase II detoxifying enzymes that play critical roles in protection against products of oxidative stress and against electrophiles. Glutathione S-transferase mu (GST-M1) and theta (GST-T1) are isoforms of glutathione transferase enzymes that participate in the metabolism of a wide range of chemicals. Deletion variants that are associated with a lack of enzyme function exist at both these loci. The frequencies of homozygous GSTM1 and GSTT1 deletion carriers are very high in most of the populations studied to date. The aim of this study was to investigate the frequencies of GSTM1 and GSTT1 genotypes among the Turabah population in Saudi Arabia in comparison with the data published for some other Arabic populations. The subjects consisted of 164 unrelated healthy individuals from the Turabah population. GST genotyping was performed by multiplex polymerase chain reaction-based (2015) methods. The GSTM1 deletion homozygosity was 56.1% and GSTT1 deletion homozygosity was 20.7%, while the GSTM1 and GSTT1 doubledeletion homozygosity was 11.0%. Comparison with published data from Bahraini, Lebanese, and Tunisian populations demonstrated no significant difference for GSTM1 between these populations. The GSTT1 null-allele frequency was significantly lower than those for the Lebanese and Tunisian populations (P = 0.001) but similar to that for the Bahraini population (P = 0.099). Characterization of GST genetic polymorphisms in the Saudi population may aid in genetic studies on the association of GSTM1 and GSTT1 polymorphisms with disease risks and the pharmacogenetics of chemotherapy.

Association of glutathione S-transferase GSTM1 and GSTT1 deletion polymorphisms with obesity and their relationship with body mass index, lipoprotein and hypertension among young age Saudis

“…The frequency of GSTT1À null genotype in the present study is comparatively lower than the other Arab populations that varied from 20% to 37%. 19,24 while in line with Turkish, 25 Indian 26 and French 27 populations. The difference in GSTT1À null genotype frequency in comparison to other Arab populations may be attributed to the different environmental conditions and natural selection processess.…”

Copy Number Variation in the GSTM1 and GSTT1 Genes and the Risk of Liver Cirrhosis in Eastern Ethiopia

“…The frequency of GSTM1 and GSTT1 null genotypes varies in different populations. Consequently, GSTM1 null genotype was more frequent in Asians (0.23 to 0.66), 16,18 Caucasians (0.45 to 0.57), 16,19 and Arabs (0.50 to 0.63) 20,21 compared to Africans (0.11 to 0.44). 19 On the other hand, GSTT1 null genotype was shown to be more frequent among Asians (0.35 to 0.52), 16,18 Africans (0.20 to 0.47) 19 and Arabs (0.20 to 0.37) 20,21 in contrast to Caucasians (0.14 to 0.28).…”

Impact of Glutathione S-Transferase Polymorphisms on Busulfan Pharmacokinetics and Outcomes of Hematopoietic Stem Cell Transplantation

“…The stage and grade of aGvHD were assessed using the Glucksberg grading system. 15 Graft loss was defined as either a lack of initial engraftment of donor cells or loss of donor cells after initial engraftment. Engraftment was defined as absolute neutrophil count >0.5 × 10 9 /L for 3 consecutive days and platelet count of >20 × 10 9 /L for 7 consecutive days without transfusion support.…”