EN A study led by the Psychiatry, Mental Health and Addictions Group at Vall d’Hebron Research Institute (VHIR) shows that genetic predisposition associated with psychiatric disorders is linked to various emotional and behavioural difficulties, even in children without a clinical diagnosis. The research was conducted in collaboration with the Mental Health area of CIBER (CIBERSAM), the Sant Joan de Déu Research Institute (IRSJD), and the Althaia Foundation, and has been published in the Journal of the American Academy of Child & Adolescent Psychiatry.

The team analysed more than 4,700 schoolchildren in Catalonia aged between 5 and 18 years. Using DNA samples from saliva, the researchers calculated the genetic risk of developing several psychiatric disorders, such as attention deficit hyperactivity disorder (ADHD), autism spectrum disorders (ASD), depression, or schizophrenia. At the same time, data on emotional well-being and behaviour were collected through questionnaires completed by the participants themselves (in the case of teenagers), their families, and teacher.

The results show that having a genetic susceptibility to develop some psychiatric disorder was associated with 35 of the 54 emotional or behavioural traits analysed. This association was particularly evident in genetic risk for ADHD, which showed the clearest and broadest link with emotional and behavioural problems in children, such as hyperactivity and attention difficulties—characteristic of the condition—but also aggression or difficulties in social interaction. These associations were observed both in assessments provided by families and in data reported by teachers and adolescents themselves.

“These findings show that genetic risk for mental disorders is associated with emotional and behavioural issues even in children who do not meet clinical diagnostic criteria,” explains Dr. Silvia Alemany, principal investigator of the Psychiatry, Mental Health and Addictions Group at VHIR and CIBERSAM.

The team also highlights the association between genetic factors predisposing to ADHD and a wide range of problems also related to other psychiatric disorders, such as autism or depression. “These are factors that are not specific to ADHD but are more transversal, and they may help us detect other psychiatric conditions,” notes Dr. Rosa Bosch, coordinator of the SJD MIND Schools program at IRSJD, member of CIBERSAM, and Head of Research of the Mental Health Area at Althaia University Healthcare Network in Manresa.

The study also revealed an association between genetic risk for ASD, depression, and schizophrenia with emotional and behavioural difficulties exclusively in boys.

This is the largest study conducted in Spain to analyze how genetic risk for mental disorders manifests in the behaviour of children and adolescents in the general school population. “These findings suggest that genetic information could be used in the future for early detection of mental health problems, long before they manifest as clinical disorders,” says Dr. Marta Ribasés, principal investigator of the Psychiatry, Mental Health and Addictions Group at VHIR and CIBERSAM.

The study was made possible thanks to funding from the Agency for Management of University and Research Grants (AGAUR), the Instituto de Salud Carlos III, La Marató de 3Cat, the European Regional Development Foundation (ERDF), the ECNP Network ‘ADHD across the Lifespan’, the “la Caixa” Foundation, the Barcelona Provincial Council, the Strategic Plan for Health Research and Innovation (PERIS), the Sant Pau Private Research Foundation (FISP), and the Catalan Department of Health.