Melanie de Wit, behavioral geneticist and researcher on autism, shows that it is not possible to reliably predict autism with DNA alone.
De Wit shows that autism arises from a complex interplay of genetic, personal and environmental factors. Her work underscores that a broader view is needed, in research and in practice.
Autism is more complex than is often thought
Autism is still often viewed from a single perspective, for example genetic. But according to De Wit, that does not do justice to reality. "In my research, I see precisely how diverse the lives of people with autism are," she says. "Differences cannot be traced back to one cause, but arise from multiple factors that influence each other." Combining DNA with information about a person's environment and personal experiences creates a more complete picture. And that is essential to better understanding autism. Genetic scores that are sometimes already offered commercially are still far too inaccurate for that.
Genetic scores: interesting, but still limited
An important part of the research focused on so-called polygenetic scores: calculations that indicate an increased likelihood of certain traits based on DNA. De Wit shows that these scores are currently not yet suitable for making statements about individual people. They can only reveal small differences between groups in research. This is relevant because commercial parties now sometimes offer this information. "My research shows that such applications are premature for now," De Wit said. "We have to be careful with expectations around DNA testing."
What does this mean in practice?
The findings have direct implications for care and policy. Professionals such as psychologists and doctors would do well not to approach autism from a single perspective. Instead, good care requires attention to the whole: personal characteristics; family background; living environment and experiences. In doing so, it is important to keep in mind the major differences between people with autism.
Data from thousands of participants
For her research, De Wit used data from the Dutch Autism Register, a long-term study in which participants complete annual questionnaires. In addition, genetic material was collected through cheek swabs, which were used to calculate polygenetic scores. These data were combined with results from literature reviews and publicly available information on environmental factors.
Careful handling of DNA
The results are relevant to people with autism, their loved ones, caregivers and policy makers. In the short term, they help make expectations around genetic research more realistic. In the longer term, genetics may be able to play a role, but only as part of a broader body of information. At a time when DNA testing is becoming increasingly accessible, this is an important message, De Wit argues: "Only by combining different perspectives can we do justice to the complexity of autism."