The National Institutes of Health (NIH) have launched a $190 million research effort to learn about epigenetics. According to Nature News ...
It’s not that epigenetics is totally useless. I just don’t see why it’s worth 190 million dollars.
Kevin Struhl
Harvard Medical School
Epigenetics, described as "inheritance, but not as we know it"1, is now a blisteringly hot field. It is concerned with changes in gene expression that are typically inherited, but not caused by changes in gene sequence. In theory, epigenetic studies can help explain how the millions of cells in the human body can carry identical DNA but form completely different cell types, and perhaps why certain cells are susceptible to disease.It seems strange to be spending so much research money on something that scientists can't even define properly [Epigenetics in New Scientist, Epigenetics Revisited, Epigenetics]. Perhaps some of this money will go toward coming up with a reasonable definition of what they're studying.
The NIH's epigenomics initiative is a plan for such studies on a grand scale including, for example, surveys in different human cell types of all the chemical tags, or epigenetic marks, that might control genes.
As far as I know we already have a good model for how totipotent cells can differentiate into many different cell types. We also understand how they can revert to pleuripotent cells. We even know that differentiated cells can be transformed back into stem cells by adding certain transcription factors.
Now we add in the fact that some DNA binding proteins can covalently modify DNA and this affects gene expression. What's the big deal?
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