Friday, November 25, 2016

A Genetic Basis for Infidelity

  Lets get this out of the way: this is not The Genetic Basis for Infidelity, that is to say that the findings reported in this article do not constitute a 'free pass' for cheaters. That being said, there is a substantial amount of information to consider when we ask the all important 'why?' of cheaters. Dr. Brendan Zeitch of the University of Queensland, Australia conducted a study of 7,400 twins, looking for a relationship between genes encoding the hormones oxytosin and vasopressin, and infidelity.  Vasopressin affects a number of human attritubutes, including trust and sexual bonding.The study found that 9.8% of males and 6.4% of females reported having two more sexual partners in one year. Additionally, a relationship between five variants of the vasopressin gene and infidelity in females was discovered. This relationship is borne out in studies of other mammals. Two species of vole(montane and prairie) studied by Dr. Thomas Insen, are known to exhibit promiscuity and monogamy respectively. The primary locations differ in each species, near the reward center in prairie voles and in the amygdala(where fear and anxiety are processed) in montane voles. Mating, therefore, results in different responses in either species. In prairie voles, it fosters attachment, but has little effect in montane voles.

Another study, conducted by Justin Garcia, looked into the impact of dopamine on infidelity. The study looked at a mutation in the D4 receptor, which results in reduced binding of dopamine. Dopamine rewards thrill seeking, which is one reason( aside from the obvious) that people find cheating appealing and tend to repeat the act. People with the D4 variation are operating at reduced dopamine levels, which may cause them to seek activities that increased their dopamine levels.

A pretty fair reporting of the body of evidence currently available concerning cheating. I would note that the title is a little more sensational than necessary. I think it takes for granted the power of a title to prime the reader's response to the material. A paper surfaced amidst some of the discoveries that led to this article, and I think it bears a read through.


  1. This is definitely an interesting concept to consider. When you think about the brain chemistry and genes that influence certain feelings and behaviors, it is understandable to see why some people may consider infidelity based on how they feel. However, I don't think that it necessarily explains infidelity, because it is a choice, but I do think that it probably has a huge influence and impact on that decision.

  2. I definitely agree that the title is a little more dramatic to draw readers in to read the article. I do not think that this necessarily means that if someone has a lack of dopamine in their body they will cheat but the chemistry and the concept of the idea do make sense. It is an interesting concept.

  3. This concept is indeed intriguing. The idea of infidelity being linked to the levels of dopamine released in the brain by the D4 gene can definitely have an influence as to why someone did what they did. However, I ultimately believe infidelity is a choice, and agree with the author when they say that one cannot justify his/her actions with the notion that their genes made them this way.