The Incidence of the XRCC1 rs25487 and PON1 rs662 Polymorphisms in a Population from Central Brazil: Patterns in an Area with a High Level of Agricultural Activity

Abstract

In Brazil, high levels of agricultural activity are re ected in the consumption of enormous amounts of pesticide. The production of grain in Brazil has been estimated to reach 289.8 million tons in the 2022 harvest, an increase of 14.7% in comparison with 2021, with an even greater increase being predicted for Goiás, one of the country's principal grain producing states. These advances are likely associated with a progressive increase in the occupational exposure of rural workers to pesticides. The PON1 gene activates the enzymes involved in phase I of liver detoxi cation. The rs662 variant of this gene is known to modify the activity of the PON1 enzyme, which can increase the susceptibility of an individual to pesticides, leading to more severe symptoms or the development of diseases. The present study describes the frequencies of the rs25487 (of the XRCC gene) and rs662 variants and their haplotypes in a sample population from Goiás, Brazil, and compares the frequencies with other populations from around the world to verify the variation in the distribution of these Single Nucleotide Polymorphisms (SNPs). The study analyzed samples taken from 494 unrelated individuals resident in the state of Goiás. The A allele of the rs25487 variant had a frequency of 26% in the Goiás study population, and the modi ed rs662 G allele had a frequency of 42.8%. Four haplotypes were recorded for the rs25487 (G > A) and rs662 (A > G) markers, with a frequency of 11.9% being recorded for the A/G haplotype (both modi ed alleles), 30.8% for the G/G haplotype, 14.3% for the A/A haplotype, and 42.8% for the G/A haplotype (both wild-type alleles). In conclusion, we demonstrated the distribution of important SNPs associated with pesticide exposure in an area that presents a high level of agricultural activity.

Chromosomal Damage, Chromosome Instability, and Polymorphisms in GSTP1 and XRCC1 as Biomarkers of Effect and Susceptibility in Farmers Exposed to Pesticides

“…Regarding the assessment of polymorphisms at exon 6 in the XRCC1 gene, we observed a predominant presence of the wild-type CC homozygous genotype in exposed and unexposed individuals. This observation is consistent with findings from previous studies [62]. Concerning polymorphisms at exon 10 of the XRCC1 gene, we observed a higher prevalence of the heterozygous genotype GA in the exposed group in comparison to the control group.…”

Contrasting patterns of DNA damage in rural workers from central Brazil: what may account for the geographical variation in genotoxicity following occupational exposure to pesticides?

“…However, the correlation with the number of pesticides, while signi cant, was relatively weak (Rho = 0.304), and applied only to %DNA, with no signi cant correlations being found in the cases of either OTM or TL. Overall, then, the most important factor determining this variation may be the intrinsic variation in the genetic pro les of the different populations, and differences in their susceptibility to contamination, as demonstrated by Alves et al (2023). To investigate this possibility, a Principal Component Analysis (PCA) for the DNA damage parameters in the different population groups was conducted (Fig.…”