BIOLOGY 3UU3 Chapter Notes - Chapter 1: X-Inactivation, Dna Methyltransferase, Dna Glycosylase
Document Summary
Epigenetics is the field of study surrounding stable alterations to the dna and histone proteins that alter gene expression. Epigenetics is the broad term used to describe a variety of reversible modifications to the genome that are meiotically and mitotically heritable. Epigenetic mechanisms provide the link between environmental factors and phenotypical changes during the whole lifetime. Results: the degree of methylation was the same regardless of the location in the genome. The genetic code of a promoter determines the methylation of surrounding cytosines on the same strand of dna: factor binding sites along the genome may also impact dna methylation patterns. For example, a mutation within a factor binding site limits the maintenance of methylation patterns in the surrounding region of dna. Hydroxymethylation as an intermediate in demethylation: an epigenetic mark called 5-hydroxymethylcytosine (5-hmc) is a proposed player in the removal of methyl groups from cytosine bases.