Epigenetics reaches fever pitch
1 Oct 2013 by Evoluted New Media
The excitement around epigenetics has mounted almost to fever pitch levels in the last five years.
In the build-up to the ENCODE study findings last year, claims and counter claims began to whizz back and forth over ‘junk-DNA’ – was this in fact the worst example of a biological misnomer in the history of science?
Despite several rumblings of discontent at both the conclusions and methodology of the ENCODE project, the consensus does seem to have shifted to uncovering how important epigenetic factors – including non-coding DNA – are rather than if they exist in the first place.
As Eric Green, director of the US National Human Genome Research Institute beautifully sums up: "The complexity of our biology resides not in the number of our genes but in the regulatory switches". And it is of course the nature of those regulatory switches which is now the focus of a huge body of research. This is epigenetics, and it is proving to be a huge challenge to uncover its full influence and mechanisms.
But one thing is now clearer than ever – the very essence of the biological blueprint appears now not to be exclusively rooted in DNA. But can we go further and begin to think of an epigenetic mechanism of heritability?
Science recently carried a tantalising report of ongoing studies of epigenetic inheritance at the University of Groningen in the Netherlands which show that methylation marks on the DNA of plants can alter the phenotype in heritable ways that remain stable up to at least eight generations.
To suggest for one second that the importance of DNA is lessened – especially in terms of heritability – would be incorrect, and would rightly have many Neo-Darwinists wagging fingers dismissively. Yet it does seem as if some evidence has now begun to suggest that traditional DNA mutation may not be the only target that natural selection can work upon.
Wrangling over heritability aside, there is perhaps a more pragmatic concern facing the research community – that of epigenotocity. Logic dictates that given epigenetics obviously plays an important role in biological function – therefore it may be a target for disruption. The substrate of epigenetics is of course molecular – and as such can potentially be manipulated and altered by other compounds. On page 20 we learn why genotoxicity must now encompass epigenetic factors.
