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In this week’s paper issue of TIME, author Judith Warner explores a provocative theory about why rates of autism, particularly the mild form known as Asperger’s, are on the rise: because people who have certain “autistic” traits are increasingly meeting and marrying each other and having offspring who are more likely to be on the spectrum.

The theory of “assortative mating” was first put forth by neuroscientist Simon Baron-Cohen, a leading autism researcher and something of a rock star in the field. He’s the first cousin of comedian Sacha Baron Cohen, and like his cousin, his prolific work tends toward the out-of-the-box. Combine that with his outspokenness — uncommon for a scientist — and it’s clear why at a recent international conference in San Diego, he was “frequently mobbed by fellow attendees and treated with near universal adulation,” Warner writes.

But back to Baron-Cohen’s mating theory. Reports Warner:

In the late 1990s, he’d come to believe that a common cognitive profile — a tendency toward what he called systemizing (focusing on systems and how they work), combined with noted deficits in empathy, or the ability to read and relate to others — existed both in people with autism and, to a much lesser extent, in many of their relatives. He’d begun to theorize that this sort of brain type would be common in any population that brought people with very strong math, science and tech skills to cluster together — and to think that if these high systemizers were choosing one another as mates, they might be particularly likely to have autistic children.

Supporting the theory, the recent upsurge in autism rates has coincided with certain social changes, including an unprecedented movement of women into math and science professions, which in turn may have encouraged the meeting and mingling of like-minded — and like-brained — future parents. The dotcom boom further raised the social capital of high systemizers, making them more sought after as mates. It’s possible that people with higher than normal levels of autistic traits have been reproducing more than ever before.

The theory is still largely speculation, shored up by seductive anecdotes about Asperger’s appearing unusually commonly in MIT alums and their children, though in a recent study in the Netherlands, Baron-Cohen found that kids living in Eindhoven — the Dutch Silicon Valley — were to two to four times more likely to be diagnosed with autism than kids in two other similar, but less tech-centric regions.

Still, Baron-Cohen is the first to caution that his results are preliminary. And, above all, he warns against drawing simple conclusions from his work about who shouldn’t marry whom. “It’s very easy to become alarmist and cause panic” he tells TIME. “It can be dangerous.”

To read more, pick up this week’s copy of TIME or use your subscription to read the full story online.

Meredith Melnick is a reporter at TIME. Find her on Twitter at @MeredithCM. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.