Genetic variants of H2AX gene were associated with PM2.5-modulated DNA damage levels in Chinese Han populations

• Subjects were from three cities and we used a meta-analysis across the three cities.
• We evaluate the contribution of SNPs to DNA damage levels with PM2.5 exposure.
• We defined the genetic variants consistently associated with DNA damage levels.
• Further evidence that H2AX is closely related to PM2.5-modulated DNA damage levels.

Exposure to particulate matter 2.5 (PM2.5) may result in DNA damage. Histone variant H2AX phosphorylation plays a central role in the response to damaged chromatin. In the current study, we investigated whether H2AX gene polymorphisms account for PM2.5-modulated DNA damage levels. A total of 307 healthy urban residents were collected from three cities in southern, central, and northern China, Zhuhai, Wuhan, and Tianjin, respectively. The dust mass concentrations of PM2.5 were detected by Gilian 5000 pumps, and the DNA damage levels were measured using comet assay. Seven potentially functional single nucleotide polymorphisms (SNPs) of H2AX gene were selected and genotyped by Illumina Infinium® BeadChip. We found that three SNPs (rs10790283 G > A, rs604714 C > A and rs7759 A > G) were significantly associated with DNA damage levels (adjusted P = 0.002, 0.018 and 0.027, respectively). Significant interactions (P < 0.05) were observed between certain genetic polymorphisms and PM2.5-modulated DNA damage levels. These results suggested that genetic variations of H2AX might be associated with the DNA damage levels in urban residents with different exposure to PM2.5. Further studies with large sample size in independent populations merit validating these findings.