When mice don’t produce the hormone oxytocin or its receptor, they lose the ability to recognize other familiar mice by their smell. Although humans use other means for identifying one another, researchers have hypothesized that oxytocin plays a role in human recognition as well. Now researchers at Emory University, along with an interdisciplinary team of scientists from University College London, Finland’s University of Tampere, and Germany’s Max Planck Institute, report links between a particular single nucleotide polymorphisms (SNP) in the oxytocin receptor gene (OXTR) and social recognition abilities in members of 198 families with a single autistic child (1).
“One feature of autism is that there is a disruption in some aspect of social cognition,” said Larry Young, Director of the Center for Translational Neuroscience at Emory University. “We chose families who had members with autism because we know that, across the whole group, there is a wide range of variability in social cognitive function.”
The researchers tested members of these families for facial recognition memory, emotional discrimination, and gaze detection and then looked at polymorphisms in the OXTR gene. None of the SNPs they found were linked to autism, but the group found one SNP, the rs237887 variant, that was strongly associated with facial recognition memory the individuals with autism as well as their family members.
“To me, this is really cool because we have previously shown that mice with a complete deletion of this gene can’t remember other mice,” he said. “But mice don’t use face recognition memory. They use olfactory recognition; they tell each other apart by smell. And this suggests that oxytocin is affecting some kind of common process across man and mouse when it comes to social recognition even though different sensory modalities are being used.”
Young argued that this provides further evidence that oxytocin is not a “cuddle chemical,” as it is often called since it is the chemical responsible for the formation of monogamous bonds, but rather a single molecule that makes social stimuli more salient in both mice and men.
“We think oxytocin helps the brain pay more attention to the fine details in social situations,” he said. “And what this study suggests is that OXTR is involved in a very fundamental smaller process of social recognition.”
1. Skuse DH, Lori A, Cubells JF, Lee I, Conneely KN, Puura K, Lehtimäki T, Binder EB, Young LJ. Common polymorphism in the oxytocin receptor gene (OXTR) is associated with human social recognition skills. Proc Natl Acad Sci U S A. 2014 Feb 4;111(5):1987-92.