Oxidation drives SNPs, recombination

Spontaneous oxidative DNA damage may drive much of human genomic diversity by inducing single nucleotide polymorphisms (SNPs) and meiotic recombination, according to a new study in Genome Research. These findings reveal a mechanism by which environmental insults and oxidative metabolism may cause genetic mutations.The authors found that an oxidized form of the DNA base guanine called 8-oxoguanine (8-oxoG) was distributed unevenly across the genome, and regions dense in 8-oxoG showed abnormally high levels of recombination and SNPs. The paper does not provide absolute proof that 8-oxoG promotes SNPs or recombination, but "it's a very reasonable speculation," said John Drake of the National Institute of Environmental Health Sciences, who did not participate in the research. "They back up their speculations with reasonable bits of evidence."Levels of DNA damage and polymorphism vary considerably across different regions of the human genome, but very little is known about what makes a region...