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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No you need to know what you're talking about when discussing flaws in the method. Northwestern Europe is very very similar genetically.
This is why precise ancestral markings distinguishing say, Danish, Germans, English are hard and there wil lbe slack
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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