I'm not sure where you've seen that, but I keep up-to-date on that (in several ways) and I have never heard that.
I just meant to bold the 'never'...
Bump for reply in a little while.
A number of years ago (10-12?), my brother was mistakenly diagnosed as schizophrenic. As a result, my mother and I were doing as much reading as we could. We weren't computerized in those days, so we were reading books. Perhaps this was a theory in vogue for awhile.
I haven't kept up on the latest, so I'll guess this is NOT valid. I'm sorry for any confusion.
I've been searching depression and sex, depression and sex and (genetics OR heredity) on PubMed and Googled depression maternal linkage. The best that I can find are A population-based twin study of lifetime major depression in men and women. and Evidence for a possibly X-linked trait related to affective illness
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