We’re currently replicating the findings of this Intel project.
A comparison of mitochondrial DNA mutations caused by exposure to Roundup® versus cadmium in the earthworm (Eisenia fetida)
Clara C. Tucker, Maria Brown, Sharon T. Pochron
Abstract
The World Health Organization reclassified the world’s most widely-used herbicide, glyphosate, as a “probable carcinogen” (WHO, 2015). The European Food Safety Authority countered by claiming that glyphosate is unlikely to pose a cancer risk (EFSA, 2015). One way to understand glyphosate’s potential carcinogenicity is to assess its ability to damage mitochondrial DNA (mtDNA) because mutations in mtDNA are associated with cancer (Baysal, 2006). However, no study has tested the effect of glyphosate or glyphosate-based formulations such as Roundup on mtDNA in any species. To rectify that, we compared the mtDNA of earthworms (Eisenia fetida) that had been exposed to cadmium to those exposed to a specific Roundup formulation (Roundup-Ready-To-Use). Cadmium both damages mtDNA and causes cancer. After sequencing the nucleotides, we generated a phylogenetic tree, hypothesizing that Roundup-exposed earthworms would resemble cadmium-exposed earthworms in terms of micro-mutations. If correct, the Roundup-exposed earthworms should group preferentially with the cadmium-exposed earthworms on the phylogenetic tree. We found that in 57.9% of the cases, Roundup caused a suite of mutations that resembled themselves but not those caused by cadmium exposure. Exposure to Roundup (26.3%) caused damage that resembled cadmium damage in 26.3% of the cases, and exposure to Roundup caused no damage to earthworm mtDNA in 15.8% of the cases. Our findings have implications for soil ecology and human health, and suggest that methods of Roundup exposure may be important in understanding its potential to damage mtDNA.