The notion that we are stuck with the genes we inherited from our parents is becoming a little cloudy. Emerging studies show that we have more control over modifying our genes than we once thought, and we can pass those modifications on to our kids and grandkids.
There’s a rapidly emerging research field centered around ‘epigenetics’. Essentially,
this is the ability to modify your genes during your life to change their level of activity. Genes, in and of themselves, are just blueprints. In order to use them you have to make the product that the genes code for. This requires ‘activating’ the gene so that it goes into production mode.
Epigenetics refers to the types of modifications we do to our genes that either crank up their productivity or dial it way down. The kicker is that these types of modifications can be heritable. Meaning, the way you modify genes during your life can be passed on to future generations. Also, the way your parents and grandparents modified their genes may have been passed on to you.
So far, we know that this applies to genes that control your eating behavior, fat storage, learning and memory, predisposition to drug addiction, and your circadian rhythms. Epigenetics have also been implicated in the risk for diseases such as schizophrenia, bipolar disorder, and maybe even Alzheimer’s, so definitely fall into the realm of keeping your brain fit.
So how do we modify our genes? This is a hot area of research. We have made great strides in understanding of how our genes are modified at the biochemical level, but we are still only scratching the surface of understanding which behaviors or experiences cause these modifications.
However, current research does support the role for a few major lifestyle factors. First, what we decide to eat can have an effect on how our genes are modified. Certainly, pregnant women partially control the modification of their unborn’s genes through dietary choices. But there is also data suggesting men’s diets can control the epigenetic modifications of their future kids and even grandkids. Second, stress levels and trauma exposure are likely to be key factors in controlling epigenetic modifications.
Okay. So the way we choose to live our lives can modify our genes and we can pass those modifications on to our next generations. But what kinds of effects are we talking about?
Again, the field is young, but there are some interesting studies out there. A new study from Chang et al. at Rockefeller University published in the Journal of Neuroscience, used rodents to show that a mother’s diet during pregnancy continues to effect their offspring well after birth. Not too surprising, but here are some interesting details.
Moms who ate a high fat diet had babies, who, after birth, showed a preference for fat (over carbohydrates), ate more when allowed to eat freely, and showed an increase in many hormones that make you feel hungry. This included hormones released from the gut and those controlling feeding behavior at the level of your brain. Not surprisingly, these baby rats grew up to be fatter teens (they didn’t follow them into later adulthood) and had higher triglycerides and higher insulin. In humans, these types of changes can link to increased risk for diabetes, heart disease and depression.
To be clear, this study was solely about mom’s diet. There were control rats, who were genetically very similar, that ate a balanced diet and their pups did not have these problems. This means that the high fat diet that mom ate caused epigenetic changes in the pups that cranked up the production of genes the led to bad dietary choices in the pups, even after mom was out of the picture.
There are a few interesting studies in humans as well that suggest these types of effects apply to us as much as our lab rat friends. And it’s not just the mother’s diet that counts, although that probably has the biggest effect. Another study found that paternal grandfathers who suffered from a famine, had grandkids with a higher risk for diabetes.
So to answer the question posed in the title of this article, yes and no. You are probably stuck with the genes you’re born with, but how you choose to use those genes (and pass them on to your children) depends on how you choose to live. Even if you are past your reproductive years, the behaviors that you instill in your kids and grandkids can alter their genes and their future generations, so why not alter them for the better?
References:
The Journal of Neuroscience (2008), 28(46):11753-11759.
The Journal of Neuroscience (2008), 28(46):12107-12119.
