Page, Esther

Discovery of the Oxytocin Receptor Gene in Titi Monkeys

Faculty Mentor: James Dee Higley, Psychology

Titi monkeys, are a new world monogamous nonhuman primate that bonds for life. Their monogamous nature makes them an ideal model for studying parenting behavior as well as social partner relationships (i.e., husband and wife). Non-human primates are comparable to humans genetically and, perhaps as a consequence of their genetic similarities, they show many behavioral parallels (Bales et al., 2007). Studies in humans show that variation in the oxytocin receptor gene (OXTR1) impacts the strength and type of a mother-infant relationship (Bakermans-Kranenburg & van IJzendoorn, 2008; Carter, 1992). While the OXTR1 has been found in a number of nonhuman primates including capuchins, marmosets and squirrel monkeys, the gene has not yet been located in titi monkeys. The primary focus of my research was to locate this gene (OXTR) in titi monkeys, and determine if it is polymorphic (meaning there is more than one variation of this region in these primates.)

While in California at the California National Primate Research Center, I had the opportunity to extract DNA from blood samples of 22 titi monkeys. I processed the DNA through well-established lab procedures including PCRs, purification, and then sequenced the specific regions where there was the highest probability of finding the comparable OCTR1 region. While a complete analysis has not yet been completed of our results, we can at this point state that the region we did sequence is the location we were looking for, and that there is a very high probability that there are polymorphisms. This being said, the implications of this research are great.

This discovery enables us study the effect of the OXTR1 gene on social behavior, especially between mothers and infants and the pair bonded mothers and fathers. By doing so, this would broaden our understanding of genetic influences on social bonds and relationships, especially those between mothers and infants, and the infant’s pair bonded parents. Early social interactions are integral in normative nonhuman primate social development and subsequent sociability (Provençal et al., 2012) Because of this, the findings from this project have the potential to help us understand and ultimately mitigate deleterious genetic effects on social functioning. Findings from this project could also influence our understanding of mother-infant bonding difficulties, their effects on the developing child, as well as spousal relationships, and other social interactions.

References

Bakermans-Kranenburg, M. J., & van IJzendoorn, M. H. (2008). Oxytocin receptor (OXTR) and serotonin transporter (5-HTT) genes associated with observed parenting. Social Cognitive & Affective Neuroscience, 3(2), 128-134.

Provençal, N., Suderman, M. J., Guillemin, C., Massart, R., Ruggiero, A., Wang, D., Szyf, M. (2012). The Signature of Maternal Rearing in the Methylome in Rhesus Macaque Prefrontal Cortex and T Cells. The Journal of Neuroscience : The Official Journal of the Society for Neuroscience, 32(44), 15626–15642.

Carter, C. S., Williams, J. R., Witt, D. M., Insel, T. R. (1992), Oxytocin and Social Bonding. Annals of the New York Academy of Sciences, 652, 204–211.Bales, K. L., Mason, W. A., Catana, C., Cherry, S. R., & Mendoza, S. P. (2007). Neural Correlates of Pair-bonding in a Monogamous Primate. Brain Research, 1184, 245–253. http://doi.org/10.1016/j.brainres.2007.09.087

Rodrigues, S. M., Saslow, L. R., Garcia, N., John, O. P., & Keltner, D. (2009). Oxytocin receptor genetic variation relates to empathy and stress reactivity in humans. Proceedings of the National Academy of Sciences, 106(50), 21437-21441