Up-to-date research from The University of Cambridge suggests that autism should not be understood as a homogeneous condition with a single cause. Researchers have found that people diagnosed in early childhood often have a different genetic profile than those diagnosed later in life, adding to our understanding of how the disease develops.
The test analyzed the behavior of autistic people during childhood and adolescence in the UK and Australia. Genetic data from more than 45,000 patients with the disease from different cohorts in Europe and the United States were also assessed.
By combining genetic information with age at diagnosis, the researchers observed that the profiles of people who were diagnosed with the disease early differed from those who were diagnosed at later stages. They found only slight overlap between the two groups, indicating that the biological mechanisms associated with autism in childhood may differ from those associated with autism identified in adolescence or adulthood.
An analysis published last week in the journal Nature found that children diagnosed before age 6 were more likely to have had behavioral difficulties from an early age, such as problems with social interactions. However, people diagnosed after the age of 10 were more likely to experience social and behavioral difficulties during adolescence. They also showed a greater predisposition to mental illnesses such as depression.
The study adds that the average genetic profile of those diagnosed later was closer to the genetic profile ADHD and conditions such as post-traumatic stress disorder rather than “classic” autism diagnosed in early childhood.
The study shows that the timing of diagnosis is not entirely random, but reflects underlying genetic differences that in some cases overlap with the risk of developing other conditions.
“For the first time, we have discovered that earlier and later diagnosed autism have different biological and developmental causes,” said Varun Warrier, a researcher at the University of Cambridge’s Department of Psychiatry and lead author of the paper. press statement. “The term ‘autism’ probably describes many conditions.”
Scientists emphasize that their intention is not to create up-to-date subtypes of autism, but to understand the various developmental processes of this disease in order to improve therapy. “Certain genetic factors predispose people to exhibit autism characteristics from a very young age that can be more easily identified, which may lead to earlier diagnosis,” Warrier says. “For others, genetic factors may influence which autism features appear and when. Some of these children may have characteristics that go undetected by parents or caregivers until they cause significant distress in late childhood or adolescence.”