• Question: What are Epigenetics and what do have with cancer?

    Asked by xeede to David on 12 Jun 2019.
    • Photo: David Wilson

      David Wilson answered on 12 Jun 2019:

      Epigenetics affects how genes are read by cells and whether the cells should produce a specific proteins. For example, the COL1A1 gene in DNA is present in all types of cells but only “expressed” in skin cells to produce Type 1 Collagen proteins.
      Epigenetics controls genes by (a) nature: epigenetics is what determines a cell’s specialisation (e.g., skin cell, blood cell, hair cell, liver cells, etc.) as baby develops through gene expression (active) or silencing (dormant); and (b) nurture: the environment around us can also cause genes to be turned off or turned on.
      Epigenetics is everywhere. What you eat, where you live, who you interact with, when you sleep, how you exercise, even aging – all of these can eventually cause chemical modifications around the genes that will turn those genes on or off over time.
      Epigenetics makes us unique. Even though we are all human, why do some of us have blonde hair or darker skin? Why do some of us hate the taste of mushrooms or eggplants? Why are some of us more sociable than others? The different combinations of genes that are turned on or off is what makes each one of us unique.
      Epigenetics is reversible. With 20,000+ genes, what will be the result of the different combinations of genes being turned on or off? The possible arrangements are enormous! But if we could map every single cause and effect of the different combinations, and if we could reverse the gene’s state to keep the good while eliminating the bad… then we could theoretically* cure cancer, slow aging, stop obesity, and so much more.
      One way that genes can be turned on or off (activated or silenced) is by a histone modification, two examples of which are methylation and acetylation. Histone modification make a gene more or less “available” to be read by the cell.
      Cancer was the first human disease to be linked to epigenetics. Research in 1983, using human tumour tissues, found that genes of intestinal cancer cells were hypomethylated compared with normal tissues.DNA hypomethylation can activate cancer causing genes, whereas DNA hypermethylation initiates silencing of tumour suppressor genes. An accumulation of genetic and epigenetic mistakes can transform a normal cell into an invasive or metastatic tumour cell. Additionally, DNA methylation patterns may cause abnormal expression of cancer-associated genes. Global histone modification patterns are also found to correlate with cancers such as prostate, breast, and pancreatic cancer. Subsequently, epigenetic changes can be used as biomarkers for the molecular diagnosis of early cancer.
      This is some really complicated science that I find difficult to understand so i hope I’ve written an answer that makes some kind of sense to you. Well done on a great question and I think your amazing if you even attempt to understand what I’ve just written.