A Mousy Mystery

In the year 2000 a simple study performed at Duke University changed the way scientists looked at genetics and DNA.  The study was set up to look at sets of so-called agouti mice which are mice that displayed an agouti gene causing the mice to be extremely obese and yellow in color.  More than this, the presence of this gene also rendered these mice much more prone to cancer and diabetes.  Almost 100% of the time, these agouti mice would give birth to offspring that also displayed the agouti gene and shared the same bleak fate.  The researchers in the study wanted to see if they could change the outcomes of these offspring by making changes in the mother mice.

Understand that the thinking before this study (and still with many today) was that your DNA is your destiny.  This way of thinking leads many to believe, “Well my Mom had a bad heart, so I will too.”  But the researchers at Duke wanted to see if this was really true.  So they took the obese, yellow agouti mother mice and for a short time before the mice were allowed to become pregnant they simply changed their diets.  They put the mother mice on a diet rich in vitamins, minerals, and other micronutrients to see if it would change the destiny of their DNA.  With the first generation, the agouti mothers gave rise to offspring that were slender and mousy brown.  Even more importantly, these offspring did not display their parents’ tendency to cancer and diabetes and therefore lived much longer.  The effects of the gene had essentially been erased.

The importance of this study is its simplicity.  The researchers did not alter the DNA of these mice with genetic therapy or any complicated procedure.  They simply exposed the mice to a healthier lifestyle and they changed the outcome of future generations.  One other point important to understand is that the offspring of the agouti mothers still shared the same genes.  What happened here is that the change in environment, or in this case lifestyle, changed the expression of these genes thereby changing the outcome.  Similar changes in your own lifestyle will invariably change the expression of your DNA to your own benefit and to the benefit of future generations.