What causes a person to be unfaithful to his or her spouse, or significant other? Why do some people have “one night stands”, while other people never decide to do so? A new study reveals that the tendency for a person to engage in these kinds of risky behaviors has something to do with their own specific genetic make up.
In a revolutionary study, a team of investigators was led by Justin Garcia, who is a SUNY Doctoral Diversity Fellow in the laboratory of evolutionary anthropology and health at Binghamton University, State University of New York. This study takes a look at sexual behavior, and matches up a person's choices with that same person's genes. The 181 young adults who volunteered to be in this study gave researchers samples of their DNA. The young adults also gave researchers a very detailed history of their sexual behaviors and intimate relationships. The results revealed that individual differences in sexual behavior could be influenced by the presence or absence of a genetic variation.
There is a gene called DRD4. This gene is a dopamine receptor. Dopamine is the chemical that is released in our brains when we feel pleasure. In the past, this gene has been linked to sensation seeking behavior, such as drinking alcohol, taking drugs, or even gambling. The people in the study who had a specific variation on their DRD4 gene were much more likely to have a history of uncommitted sexual activity, which included both “one night stands” as well as acts of infidelity.
The reason? It has something to do with seeking out a dopamine rush. The people with this gene variant feel pleasure when they take risks. This can motivate that person to make behavioral choices that are going to trigger that rush, because it, in itself, is a pleasurable experience. It is very risky to have a “one night stand” with a complete stranger. It is risky to be in a committed relationship, and attempt to have a sexual relationship with another person outside of that committed relationship. What if they get caught? The risks are both physical, and psychological.
Now, this doesn't excuse the behaviors, it simply explains some of the motivation behind them. Not everyone who has this gene variant is absolutely going to become a cheater. Not everyone who does not have the gene variant is going to always be unquestionably faithful. There are some factors involved other than genetics. However, this study is the first to discover a genetic reason behind why some people cheat, while others do not.