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Influence of GSTT1 Genetic Polymorphisms on Arsenic Metabolism
Molly L Kile1, E Andres Houseman1, Quazi Quamruzzaman2
1Oregon State University, College of Public Health and Human Sciences, Corvallis, OR.
Journal of the Indian Society of Agricultural Statistics. Indian Society of Agricultural Statistics
|February 11, 2014
Summary
Genetic factors influence arsenic metabolism and toxicity. Individuals with GSTT1 null genotypes may face higher arsenic-related health risks due to altered arsenic excretion and methylation patterns.
Area of Science:
- Environmental Health
- Toxicology
- Human Genetics
Background:
- Arsenic exposure from drinking water is a global health concern.
- Arsenic metabolism varies among individuals, influenced by genetic factors.
- Understanding these variations is crucial for assessing arsenic-related disease risk.
Purpose of the Study:
- To investigate the impact of arsenic exposure and genetic polymorphisms (GSTT1, GSTM1) on arsenic metabolism biomarkers.
- To evaluate gene-environment interactions in arsenic exposure.
- To identify genetic factors influencing susceptibility to arsenic toxicity.
Main Methods:
- Repeated measures study in Pabna, Bangladesh.
- Measurement of drinking water arsenic (ICP-MS) and urinary arsenic species (HPLC, HGAAS).
- Analysis using linear mixed effects models to assess effects of water arsenic, GSTT1/GSTM1 polymorphisms on arsenic biomarkers and methylation indices.
Main Results:
- Drinking water arsenic positively correlated with total urinary arsenic and total methylation index.
- Significant gene-environment interaction: GSTT1 null individuals showed higher arsenic excretion.
- GSTT1 null genotypes exhibited higher primary and lower secondary methylation indices, suggesting altered arsenic metabolism.
Conclusions:
- GSTT1 genotype influences arsenic metabolism and excretion variability.
- GSTT1 null individuals may have increased susceptibility to arsenic-related toxicity due to altered methylation patterns.
- GSTM1 genotype did not show significant associations with arsenic methylation indices.
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