Abnormal DNA Methylation in the Human Genome essays

Abnormal DNA Methylation in the Human Genome essays The methylation of DNA serves as one of the most crucial epigenetic modifications of modern day genetics. Methylation and demethylation of DNA have profound effects on cellular differentiation and processes such as transcription, gene expression, chromatin structure, and suppression of invasive and unwanted genes. Many enzymes work coherently to regulate methylation activity, one of the main being DNA methyltransferase. Any disruptions in the methyltransferase pathway can lead to the modification of regular DNA methylation. The modification of these processes can lead to fatal diseases and various types of cancer. The two patterns in which atypical DNA methylation fall are hypermethylation and hypomethylation. Relevantly, the cancer genome is quite regularly marked by the hypermethylation of specific genes simultaneous to the decrease in 5-methyl cytosine levels (hypomethylation). Hypermethylation refers to the over methylation of some genes which results in the repression of transcription. Hypomethylation is a decrease in the methylation of cytosine and adenosine residues in DNA. The decrease in methylation causes the reduction of imprinting and the instability of chromosomal structure. Both patterns of abnormalities of DNA methylation can result in irregulation of gene transcription, which can ultimately lead to the development cancer; however, due to its characteristic of being reversible, modulation of methylation and methyltransferase is an ideal theraputic and epigenetic target for the various cancers that originate from it. DNA methylation was first discovered in 1948, and ever since, has generated a substantial amount of controversy as a result of trying to decipher its significance. The methylation of DNA is a covalent modification which results in the addition of a methyl group to 'the 5th carbon of the cytosine ring. Most of the methylation occurs in the CpG dinucelotide; however, since there can be up to 1...