Genetic Variants Linked To Empathy Also Play Role In Autism
How empathic we are is not just a result of our upbringing and experience but also partly a result of our genes, a new genome-wide association study from the University of Cambridge suggests.
Empathy has two components. The ability to recognize another person’s thoughts and feelings, and the ability to respond with an appropriate emotion to someone else’s thoughts and feelings. The first part is called cognitive empathy, and the second part affective empathy.
Previous research has shown that some of us are more empathetic than others, and that on average, women are slightly more empathetic than men. It also showed that, on average, autistic people score lower on the EQ, and that this was because they struggle with cognitive empathy, even though their affective empathy may be intact.
Fifteen years ago, a team of scientists at the University of Cambridge developed the Empathy Quotient (EQ), a brief self-report measure of empathy. The EQ measures both parts of empathy.
In this new study, the Cambridge team, working with the genetics company 23andMe and a team of international scientists, report the results of the largest genetic study of empathy using information from more than 46,000 23andMe customers. The customers all completed the EQ online and provided a saliva sample for genetic analysis.
Schematic diagram of the study protocol Credit: Varun Warrier, et al. CC-BY
There were three important results. First, it found that how empathetic we are is partly due to genetics. Indeed, a tenth of this variation is due to genetic factors. This confirms previous research examining empathy in identical versus non-identical twins.
Second, the new study confirmed that women are on average more empathetic than men. However, this difference is not due to our DNA as there were no differences in the genes that contribute to empathy in men and women.
This implies that the sex difference in empathy is the result of other non-genetic biological factors, such as prenatal hormone influences, or non-biological factors such as socialisation, both of which also differ between the sexes.
Finally, the new study found that genetic variants associated with lower empathy are also associated with higher risk for autism.
Small But Important Role
The study was led by Varun Warrier, a Cambridge PhD student, and Professors Simon Baron-Cohen, Director of the Autism Research Centre at Cambridge University, Thomas Bourgeron, of the University Paris Diderot and the Institut Pasteur, and David Hinds, Principal Scientist at 23andMe.
“This is an important step towards understanding the small but important role that genetics plays in empathy. But keep in mind that only a tenth of individual differences in empathy in the population are due to genetics. It will be equally important to understand the non-genetic factors that explain the other 90%,”
Varun Warrier said.
“This new study demonstrates a role for genes in empathy, but we have not yet identified the specific genes that are involved. Our next step is to gather larger samples to replicate these findings, and to pin-point the precise biological pathways associated with individual differences in empathy,”
Professor Thomas Bourgeron added.
“Finding that even a fraction of why we differ in empathy is due to genetic factors helps us understand people such as those with autism who struggle to imagine another person’s thoughts and feelings. This can give rise to disability no less challenging than other kinds of disability, such as dyslexia or visual impairment. We as a society need to support those with disabilities, with novel teaching methods, work-arounds, or reasonable adjustments, to promote inclusion,”
Professor Simon Baron-Cohen said.
There are several key challenges in the field, Varun Warrier, currently a PhD student at the Autism Research Centre, said;
“First, we have identified only a fraction of the genes associated with autism. Second, no two autistic people are alike. Third, within the spectrum autistic people have different strengths and difficulties. Finally, those with a clinical diagnosis blend seamlessly into those in the population who don’t have a diagnosis but simply have a lot of autistic traits. We all have some autistic traits – this spectrum runs right through the population on a bell curve.”
The work was funded and supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research, Care East of England at Cambridgeshire, and Peterborough NHS Foundation Trust.