For years everyone has had an opposing explanation for how our behaviors develop as we grow up. Are we born with our bad qualities through our genetics or do they come about from things like bad parenting?
It seems the answer is much clearer than we would assume. It has been known for years now that epigenetic change can be passed down from parent to child following one generation and on to the next. According to one study from Randy Jirtle of Duke University when female mice are fed a diet rich in methyl groups the fur pigment of their offspring is altered permanently. This happens without any change to the DNA at all. These changes were inherited just like we would inherit a gene mutation, without the gene mutation.
Michael Meaney came up with a hypothesis back in 1992 that has been the basis of a ton of research we now have today. His hypothesis was ‘If diet and chemicals can cause epigenetic changed, could certain experiences – child neglect, drug abuse, or other severe stresses also set off epigenetic changes to the DNA inside the neurons of a person’s brain?’ Because of this, we were able to find that traumatic experiences in our past or in our recent ancestors’ past leave molecular scars adhering to our DNA.
These experiences, while they can be forgotten, are all literally still a part of us. They become a part of us and are essentially a molecular residue. Our DNA remains the same but psychological and behavioral tendencies are inherited. If Grandma has depression, it is likely you will too.
There have been lots of studies done on this, quite a few by Meaney himself as well as Szyf. They have continued to find evidence of epigenetic changes to many other genes in the brain and have made lots of progress when it comes to this subject. Wouldn’t it be nice if we could just take a drug and wash away all of the negative things being passed down to us? Who knows, maybe someday we will be able to. To learn more on this topic click here.