Talk:Evolution of Vitamin C

"Some scientists think that the loss of human ability to make “vitamin C” may have caused Homo sapiens' rapid evolution into modern man (Challen et al., 1998; Benhegyi et al., 1997; Stone, 1979)."
 * This sounds pretty interesting, but if it's going to be sourced, shouldn't there be a copy of this research available online to validate it properly? I'm also interested into reading further on these theories, like why a lack of ascorbate would cause evolution. Is it because we developed compensatory processes? Perhaps, out of an obligation to have to eat fresh food, or have to eat fresh meat, it no longer left an options for scavengers to survive as they would get scurvy. Perhaps other components in these fresh foods had the factors needed for evolution, or it was simply a very dangerous sort of environment. You have to wonder how it relates to the development of farming in the form of planting fruit seeds. Tyciol 11:20, 24 June 2007 (UTC)

'''I think you are right! Moreover your hypothesis, that I share,''' I would report herein the abstract of Challem and Taylor's paper (1998):

http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=9655531&dopt=Abstract

Challem JJ, Taylor EW. Free Radic Biol Med. 1998 Jul 1;25(1):130-2.

Retroviruses, ascorbate, and mutations, in the evolution of Homo sapiens.

"Mutations, induced by free radicals, provide a rich molecular palette that other evolutionary forces can select for or against. A recent hypothesis proposed that large numbers of free radicals were produced when, millions of years ago, Anthropoidea lost the ability to produce endogenous ascorbate, increasing the frequency of mutations and accelerating the evolution of higher primates. Recognizing that retroviruses have been active throughout the period of primate evolution, we suggest that an endogenous retrovirus or other retroviral-like element may have been involved in mutating the gene coding for gulonolactone oxidase (GLO), the terminal step in ascorbate synthesis, approximately 45 million years ago. This possibility is supported by the presence of Alu elements (a common primate retroelement) adjacent to the site of a missing segment of the nonfunctional GLO gene. Although Homo sapiens and other higher primates produce other endogenous antioxidants, including superoxide dismutase and uric acid, they do not quench the same radicals as ascorbate and cannot fully compensate for a lack of endogenous ascorbate. As a consequence, a retrovirus may have played a pivotal role in primate and H. sapiens evolution, and the absence of endogenous ascorbate may be continuing to accelerate the rate of H. sapiens and primate evolution."

Regards

Sebastiano Venturi

Merge with Evo of Vit C
There are probably a few thousand antioxidants, several hundred classes of them, vitamin C is just one, so they are diff topics!! Sorry...based on the titles they are totally diff topics, but content very similar! 71.117.93.160 (talk) 17:59, 15 December 2007 (UTC)