http://goo.gl/qzAV9S
Having overweight parents significantly increases your risk of obesity, but the inheritance of specific mutations can't always explain why this is the case. In a study published January 28 in Cell, researchers show that differences in gene expression and not the DNA sequence play a key role in determining one's predisposition to obesity. In genetically identical mice and human twin pairs, epigenetic marks altered the activity of weight-control genes to produce distinct subpopulations of lean and obese individuals. The findings reveal a key role for an epigenetic switch in explaining individual differences in obesity.
In the end, this research could have important clinical implications. "These findings set a new playing field for disease-associated epigenetic effects," Pospisilik says. "Previously, people would have thought that epigenetics can moderately increase or decrease traits of an organism, and that epigenetic therapies could then alter or combat these shifts. Our study shows that these shifts may not only occur along a continuum, but may also have areas of high stability. This suggests the possibility that we may be able to switch physiology to produce a state that is inherently stable to stay lean or obese."