Here is video of me discussing this issue on 9News:
Click here to watch the video if it does not appear above.
It is hard to believe that personality traits are genetic. We all know people whose personalities are very different from their parents, after all.
In order to clear up some confusion about what it means to have a gene for procrastination (or anything else for that matter), here are five facts that might help:
1. There is a difference between a person's genotype (his/her genetic make-up) and that person's phenotype (his/her set of observable characteristics that are dictated by both genes and environment).
For example, a person's genes dictate, to some extent, how tall he will be. But, if he was malnourished as a child, he will be shorter than if he was well-fed.
The same is true of personality characteristics. Many are genetically linked, but the environment in which a person grows up strongly influences the expression of those genes.
2. Most studies have shown that, with regard to personality and intelligence, genes account for about 50% of a person's phenotype and the environment accounts for the other 50%.
3. Many genetic personality traits are linked to the same gene--one that controls the number of dopamine receptors we have in our brains.
Dopamine is a neurotransmitter that gives us a highly pleasurable sensation when it is released. Depending on genetics (and the environment in which we grow up) the number of dopamine receptors in our brains can vary. Here is a quick list of some of the personality traits that have been specifically linked to the dopamine gene:
4. Remember all that information about Dominant and Recessive genes that you learned in high school biology class? Most genes don't actually work that way. At least not completely.
Genes are messy. Some are recessive. Some are dominant. Some cross over. Some mix with one another. A good example of this can be seen in the children of multiracial families. When a person with dark skin has children with a person with light skin, very often their children have skin tones that are somewhere in between the two parents. We know skin tone is genetic and if it were a strictly dominant/recessive issue, the children would end up having skin tone exactly like that of one of their parents.
5. Genes are not our (complete) destiny. With certain traits, such as height or intelligence, our genes dictate an upper limit--under ideal environmental circumstances, our genes will flourish and allow us to achieve our full potential. And, if we have 'bad' genes (like a gene for Diabetes), those genes may make it easier to get sick. But, our environment plays a huge role in the expression of our genes (our phenotype). So, you may have a slightly harder time solving a puzzle, or finishing a project on time, or avoiding certain diseases. But, living a healthy lifestyle can go a long way toward manipulating your phenotype in a positive way.
And, as parents, you have a lot of control over how your kids develop, so try not to mess them up too badly.
Thanks for reading-- Max Wachtel, Ph.D.