Genetics and Epigenetics – Angela Wall

Until recently it was believed that all of our characteristics were determined by the genetic code in the DNA inherited from our parents.

It is now known that we have an ‘epigenome’ composed of ‘epigenetic tags’, chemicals that attach themselves to the DNA and histone in the chromosomes. The ‘tags’ can switch genes on or off and cause changes in our characteristics without changing the DNA code itself. These chemical ‘tags’ are acquired during the development of the embryo and throughout our lives as a result of environmental changes and lifestyle. Although they are the main way in which our many different types of cell develop, they can also cause medical conditions such as cancers and autoimmune diseases. The hotly debated issue of the moment is whether these chemical ‘tags’ acquired during our lifetime can be passed on to our offspring. There is some evidence that they are inherited, but many scientists remain sceptical and much more definitive proof is needed before we can say that the sins of the father are inherited.