Genes play a role in arsenic poisoning

According to a recent report, a large-scale genomic study in Bangladesh has found genetic deviations that regulate arsenic metabolism and increase the risk of skin lesions from prolonged exposure to arsenic. Shockingly since the 70s when hand pumps were installed to access groundwater over 77 million Bangladeshis have been exposed to toxic levels of arsenic, effectively the largest mass poisoning of a population in history according to WHO.

However researchers discovered that certain individuals have the genetic ability to convert the arsenic into a less toxic form and are less prone to developing arsenic-related diseases like skin lesions, diabetes, cardiovascular (Myocardial Infarction) and respiratory illness.

In a quest to find out why some individuals seems to have a higher risk of developing disease after arsenic exposure, the new study decided to genotype (study the genetic constitution) almost 3,000 Bangladeshis for variants throughout the genome and discovered that genetic variants linked to arsenic metabolite levels and the risk of skin lesions in the region of a likely candidate gene is due to arsenite methyltransferase, an enzyme that is critical for arsenic metabolism.

After researchers examined the gene expression levels, they discovered that those same variants were linked to a reduced expression of the enzyme, and that boosting the arsenic metabolism could potentially be an effective intervention in those individuals exposed to the toxin and those with a high genetic risk from arsenic-related disease.

This research also showed how large-scale genomic studies are possible in a largely rural population of a developing country.