DNA has long been regarded as the heritable material that encodes the instructions for the development of all known organisms. There is no doubt of its importance to life, and its role in evolution is equally fundamental.
Since the seminal works of researchers including Charles Darwin and Gregor Mendel, it is a widely held belief that changes in gene expression that develop through life experience can not be passed on the next generation. That, barring mutation, there is an unaltered continuity of the germ line.
But is DNA the whole story when it comes to inheritance? The study of non-genetic inheritance has a long history of controversy. From early 20th century scientific scandals to very recent findings, the story of nature vs nurture has fascinated many generations of scientists.
And it seems we have again arrived at a major turning point in our understanding.
Some experiences are harder to forget than others.
The genome's ability to adapt to environmental changes also has a dark side. Emerging research is beginning to unravel an extraordinary phenomenon of cellular memory centred on the field of chromatin biology. One where periods of challenging metabolic conditions can initiate programs of gene expression that dramatically increase the risk for disease later in life.