10/20/2025
I have long said that there are many ways to be autistic. Studies have shown at least 128 different genes associated with autism - and some autistics don't have any of those gene mutations.
Now science is catching up to what clinicians and autistic folks have already known for years...autism is a heterogeneous cluster of traits with many presentations.
Autism is more than just a single condition, according to a major new study of over 45,000 people across several countries.
Researchers found that people diagnosed with autism later in life—during late childhood, adolescence, or early adulthood—may have a different form of autism than those diagnosed earlier, typically before age six.
The study discovered that early- and late-diagnosed individuals tend to follow different developmental paths and even have different genetic profiles. Those diagnosed later often share some genetic traits with people who have ADHD, which might explain why it's sometimes hard to tell the two conditions apart.
Children diagnosed early usually show more behavioral challenges when they’re young, but these issues often become more manageable over time. However, those diagnosed later often face increasing behavioral difficulties and are more likely to develop mental health conditions like depression or PTSD as they grow older.
The researchers stress that autism doesn't come in just two forms. Instead, it’s likely a broad spectrum influenced by different combinations of genes, leading to a wide variety of symptoms and experiences.
Cultural factors, access to healthcare, gender, stigma, and ethnicity also play a role in when and whether someone gets diagnosed, making autism even more complex.
Understanding these different patterns, the researchers say, could lead to better, more personalized support for autistic people at all ages.
Source: Zhang, Xinhe, et al. "Polygenic and developmental profiles of autism differ by age at diagnosis." Nature (2025): 1–12.
