DNA tests like 23AndMe and Ancestry are laying bare the frightening extent of incest in the US - including woman who discovers her ex-lover was her BROTHER
While these tests, can't say explicitly whether someone is the product of incest, the results can be taken to a third party genetic testing firm which can.
The prevalence of incest in the US, with research including common genealogy test, currently puts the rate at one in 7,000. This is far more common than previously thought.
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