Beyond DNA code: epigenetics
Why is it that if you keep an active mental life by playing complicated board games or learning a language, or if you keep physically fit, you are less likely to succumb to dementia?
A/Prof John Kwok is addressing this question by looking at how lifestyle can alter the function of genes related to dementia.
To do this, he is engaging with the burgeoning field of epigenetics. Genes have to be expressed (i.e. switched on or off) in a tightly regulated manner for our bodies to function correctly. For example, genes get switched on and off when we are born, or when we hit puberty, in response to hormones or tissue growth. While there are parts of our DNA that control how genes are switched on, there are also epigenetic factors, outside our DNA, that can do this. These factors act like a dimmer switch that changes the brightness of a light.
Diet, exercise, and mental activity can ‘dim the brightness’ of genes that might lead to illness, or enhance genes that promote brain health. Not only do these lifestyle factors change gene expression, but their effect might be inherited by the next generation, even if the relevant gene’s DNA sequence itself is not inherited. Understanding the mechanisms of how this happens is a focus of many areas of NeuRA’s work. The study of epigenetics is important in exploring new possibilities for health care.