Chronic Mercury Exposure and Polymorphism in Munduruku Indigenous from Brazilian Amazon.

Genetic polymorphisms may be involved with mercury levels and signs and symptoms of intoxication from this exposure. Therefore, the aims were to describe the frequency of the polymorphism and to evaluate its effects on mercury levels and neurological signs in three Munduruku indigenous villages in the Brazilian Amazon. One-hundred-and-seven indigenous (over 12 years old) were included and genotyped (rs1695) using a TaqMan validated assay. Then, associations were evaluated by binary logistic regression, using odds ratios (OR) and 95% confidence intervals (CI). Mean age was 27.4 ± 13.9 years old, 52.3% were male, mean hair mercury concentration was 8.5 ± 4.3, exceeding the reference limit (≥6.0 µg/g), and were different among the three villages: 13.5 ± 4.6 µg/g in , 7.4 ± 2.3 µg/g in and 6.9 ± 3.5 µg/g in . The minor allele frequency of was significantly different among the villages: 57% 21% and 15% Finally, after adjustment, and genotypes were associated with lower levels of Hg (OR = 0.13; CI95% = 0.03-0.49) and abnormal somatosensory signs (OR = 3.7; 95%IC = 1.5-9.3), respectively. In conclusion, monitoring this population is imperative to identify individuals at higher risk of developing signs of chronic mercury exposure based on the genetic profile.