Ghost In Your Genes: Epigenetic Analysis

The BBC documentary, “Ghost in Your Genes,” introduces a revolutionary scientific concept that makes the Human Genome Project of the 1990’s, referred to as “one of the most outstanding scientific achievements in history,” look like only a miniscule part of what is really, a much bigger picture. Following the completion of human genome sequencing, it was discovered that humans share almost 99% of their genome with chimpanzees, thus baffling the scientific world as to how we could possibly share so much of our genome with something so immensely different from us. This difference was soon attributed to a concept known as epigenetics.

Epigenetics literally translates to “just above the genome.” In other words, the epigenome tells the genome what to do (i.e. what genes to activate, silence, etc). The process occurs via epigenetic changes – covalent modifications to the genome, that don’t actually change the DNA sequence itself, but simply leave tags that control gene expression. Epigenetic changes occur via two processes. The first is by chemically altering the DNA molecule by adding a methyl

Thus, each one has its respective effect on the epigenome. In most cases however, upon exposure to the toxin during a sensitive stage in one’s life, the toxin will result in an epigenetic modification, such as the down-regulation of the methylation of cytosine residues on DNA molecules that are normally responsible for gene silencing. The result is the activation of genes that are normally not expected to be active, and thus a complete restructuring of the epigenome; a restructuring bound to be transmitted to one’s progeny. Individuals exposed to environmental toxins exhibit a restructuring of their epigenome in a way as to allow unexpected, diseased phenotypes such as cancers, reproductive and immune problems,