New research finds genetic differences between people with autism who are diagnosed in childhood and those who are diagnosed as adults. — 123rf
People who are diagnosed with autism later in life could have a different form of the condition than those diagnosed during childhood, a large study said on Oct 1 (2025).
The new research said it provides “further support for the hypothesis that the umbrella term ‘autism’ describes multiple phenomena” that affect people differently.
For a long time, autism was considered to be a condition diagnosed in young children.
However, as the way autism is diagnosed has been expanded in recent decades, the condition has increasingly been identified in older people.
There are two theories that could explain the difference between these two groups, the researchers said.
One is that all people with autism have a similar underlying genetic profile, but some are not diagnosed during their youth because their symptoms might be more mild or subtle, and only become more noticeable later on.
The other explanation could be that autism diagnosed during childhood and later on are actually different forms of the condition.
The study published in the science journal Nature supports the latter theory.
After comparing the genetic profiles of thousands of people with autism in Denmark and the United States, the researchers determined there were significant genetic differences between those diagnosed earlier or later.
“People diagnosed with autism later in life are genetically more similar to those with attention deficit hyperactivity disorder (ADHD),” said study co-author and France’s Pasteur Institute researcher Dr Thomas Bourgeron.
Those diagnosed later in life also appear to be more at risk of mental health conditions such as depression, the study said.
People with autism are “very different from one another”, Dr Bourgeron emphasised, calling for each patient to receive care tailored to their particular needs.
Britain’s University College London emeritus professor of cognitive development Dr Uta Frith, who was not involved in the study, said she was hopeful that in the future, even more subgroups within autism “will come to light, and each will find an appropriate diagnostic label”.
“If there is talk about an ‘autism epidemic’, a ‘cause of autism’ or a ‘treatment for autism’, the immediate question must be: which kind of autism?” – AFP
