The present study examined the extent to which human processing of facial age is impacted by single nucleotide polymorphisms (SNPs) within two genes involved in the secretion and intracellular signal transduction pathways of the neurohormone oxytocin. Although such polymorphisms have been found to reliably and differentially predict participants' performance on a variety of social cognitive abilities, the impact of two markers present in the human OXTR and CD38 genes, respectively --rs53576 and rs3796863 -- has not yet been assessed in the context of facial age recognition ability. Young adult participants were directed to complete a computerized facial age discrimination task presenting faces of five age ranges (i.e. 1-4,5-8,9-12,13-17,18-22 years of age) and both male and female gender. Participants' genetic material was additionally sampled at this time. Preliminary findings indicate, consistent with trends in previous literature, that participants homozygous for the G/G rs53576 allele in OXTR are more accurate in their facial discriminations compared to those possessing the G/A and A/A genotypes. In addition, participants' performance on the facial discrimination task indicated significant effects for stimulus age and gender independent of participant genotype, with younger faces and male faces being identified more accurately, on average.
Gross, T. J. (2014). Single Nucleotide Polymorphisms (SNPs) of the Oxytocin Receptor (OXTR) and CD38 Genes Impact Perception of Facial Aging in Humans (Undergraduate honors thesis, University of Redlands). Retrieved from http://inspire.redlands.edu/cas_honors/7