A group of researchers from the National University of Singapore (NUS) has found that young adults who have higher expression of the CD38 gene as well as differences in CD157 gene sequence are friendlier and more socially adept than others. They have more close friends and show greater social skills. CD38 and CD157 genes regulate the release of oxytocin, the paramount social hormone in humans involved in primary social behaviours such as pair–bonding, mating and child–rearing, to more sophisticated behaviours such as empathy, trust and generosity.

This novel study of gene expression supports the increasing importance of the oxytocin network and its impact on shaping social and communication skills that are important for building friendships.

The findings were published in the journal Psychoneuroendocrinology.

The study was conducted by Professor Richard Ebstein and recent NUS PhD graduate, Dr Anne Chong, from the Department of Psychology at NUS Faculty of Arts and Social Sciences, along with Professor Chew Soo Hong from the Faculty’s Department of Economics and Professor Lai Poh San from the Department of Paediatrics at NUS Yong Loo Lin School of Medicine.

The team studied over 1,300 healthy young Chinese adults in Singapore in a non–clinical setting. They investigated the correlation between the expression of the CD38 gene and CD157 gene sequence, both of which have been implicated in autism studies, and an individual’s social skills as captured by three different questionnaires. These questionnaires evaluated the participants’ overall ability to engage in social relationships; their value on the importance of and interest in friendships as well as the number of close friends/confidants they have.

The results from the study showed that participants with higher expression of CD38 have more close friends, and this association was observed more prevalently among the male participants.

Interestingly, the researchers found that a variation in the CD157 gene sequence that was more common in autism cases in a Japanese study, was also associated with the participants’ innate interest in socialising and building relationships.

The evidence suggests that oxytocin, and the CD38 and CD157 genes that govern its release, contribute to individual differences in social skills from one extreme of intense social involvement to the other extreme of avoiding social contacts with other people that is one of the characteristics of autism. There is no cause for worry however, as the researchers note that majority of people are in between the two extremes.

The researchers found that higher expression of the CD38 gene and differences in the CD157 gene sequence account for 14 per cent of the variance in social skills in the general population – a remarkable finding, especially since typically less than two per cent of findings in behavioural genetic association studies rely on genetic variations alone.

Findings contribute towards possible future intervention therapies or treatments for individuals with special needs. For instance, while there is already considerable research interest in using oxytocin therapy to improve the social skills of individuals with autism, the results so far have been mixed. The findings in this study point to an alternative research direction towards treatments based on new drugs that may mimic or enhance the functions of the CD38 and CD157 genes.