https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5705608/
"In their third commentary, Samsel and Seneff create multiple syllogisms based on the fact that glyphosate can chelate manganese (Mn) (
13). At face value, there is merit in this supposition, since glyphosate was originally patented and used as a divalent cation metal chelator (US Patent No. 3160632A). These authors propose that the dysregulation of Mn homeostasis by glyphosate chelation could cause osteoporosis and osteomalacia (because bone mineralization depends on Mn), seizures (associated with reduced serum Mn), and prion diseases (since the prion protein, PrP, can misfold following binding to Mn instead of Cu). They also claim that large-scale environmental damage, such as the collapse of coral reefs, may in fact be due to glyphosate because coral mucus contains sulfated glycoproteins similar to chondroitin sulfate, whose synthesis is dependent on Mn. However, the conclusions from this commentary are speculative since the effects of glyphosate on metal micronutrient homeostasis have never been characterized. Samsel and Seneff propose that glyphosate chelation of Mn can promote binding of this nutrient metal to PrP, causing it to misfold, and rendering it capable of catalyzing metal-free aggregation of this protein (
28), which in turn could lead to prion disease. However, the sequestration of Mn by glyphosate would effectively make it unavailable to participate in interactions with other substances including proteins, making it unable to bind in place of Cu to PrP to promote misfolding and prion disease as suggested.
Indeed, based on the arguments presented, chelation of Mn by glyphosate would be protective against, rather than a causative agent of, prion disease as this would prevent this divalent cation from binding to PrP.
Out of the 328 references quoted in these authors’ third commentary (
13), which are used to support their proposal of a link between Mn chelation by glyphosate and chronic diseases,
only one study reports the effects of glyphosate on Mn levels in animals (
29). This investigation looked at a possible connection between urinary concentrations of glyphosate and Mn, and health indicators in Danish dairy cows. The results revealed a correlation between markers indicative of a disturbance in kidney function and glyphosate urinary concentration; i.e., the higher the levels of glyphosate found in the urine, the greater the indicators of kidney dysfunction. However, although Mn levels were abnormally low, they were not correlated with urinary glyphosate levels. Although no doubt interesting additional studies are required to clarify the mechanism of the observed low levels of Mn in these farm animals. Thus, this study (
29) cannot be used to conclude on an effect of glyphosate on Mn homeostasis.
The conclusions of the third commentary by Samsel and Seneff are thus unsupported by evidence."
Additional work by Dr. Michael Antoniou specific to this topic is below. It should be noted that Dr. Antoniou has been very vocal and public about his opposition to the use of Glyphosate and some of it's impacts to human health. So he's not some paid shill of "big ag". But he proves that facts matter, and the fact is he was not able to link glyphosate to be a causal factor in prion diseases via glycine to glyphosate substitution in proteins.
https://gmwatch.org/en/106-news/lat...d-into-the-proteins-that-structure-our-bodies