Thread, with interesting bit on how "science" is opportunistically suited to political needs of the time:https://twitter.com/dubsteppenwolf/status/881196329808080897 …
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However if test someone from say, Portugal and someone from England, the differences will be very clear. If African or Chinese even more so
Again, without knowing anything about the field you are as liable to be defrauded by the opponents as others are by proponents.
As for forensic DNA matching? Well that is 99.99999% accurate because we aren't tracing ancestry, simply matching two samples.
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