... to synthesis of polyamines or radical formation. SAM is regenerated from demethylated SAM via the methionine cycle, which involves folate. Imbalance of this cycle in humans, e.g. through folate shortage via dietary insufficiency, alcohol abuse, arsenic poisoning or hereditary factors, leads to depletion of SAM...

..., and hence the colonic crypt within which it occurs. Preliminary studies with a rodent model suggest the rate of age-dependent methylation of ESR1 is modifiable by dietary folate. Regions of the genome with a high density of the CpG dinucleotide, termed CGI (CpG islands), occur frequently in the promoter...

... in [ 10 ]). Prader–Willi, Angelman's and Beckwith–Wiedemann syndromes all result from abnormal demethylation of the silenced allele of imprinted genes causing biallelic expression. Abnormalities in folate metabolism and DNA methylation have been associated with Down's syndrome, and aberrant DNA...