Conserved non-coding sequence degenerate sequences with no biological function. An example of a pseudogene is the gene for L-gulonolactone oxidase, a liver enzyme necessary for biosynthesis of L-ascorbic acid (vitamin C) in most birds and mammals, but which is mutated in the haplorrhini suborder of primates, including humans which require ascorbic acid or ascorbate from food. The remains of this non-functional gene with many mutations is still present in the genomes of guinea pigs and humans. Ultraconserved regions (UCRs) are regions over 200 bp in length with 100% identity across species. These unique sequences are mostly found in noncoding regions. It is still
Vitamin C infection. The mega-dosing theory is to a large degree discredited. Modest benefits are demonstrated for the common cold. Benefits are not superior when supplement intakes of more than 1,000 mg/day are compared to intakes between 200 and 1,000 mg/day, and so not limited to the mega-dose range. The theory that large amounts of intravenous ascorbic acid can be used to treat late-stage cancer is - some forty years after Pauling's seminal paper - still considered unproven and still in need of high quality research. However, a lack of conclusive evidence has not stopped individual physicians from prescribing intravenous ascorbic acid