Medieval mass burial shows much earlier origin of Ashkenazi genetic bottleneck

I wish that the article would have addressed (in one paragraph, at least) the reason behind the inference of the genetic bottleneck.<p>But the Internet comes to the rescue:<p><a href="https:&#x2F;&#x2F;systemsbiology.columbia.edu&#x2F;news&#x2F;study-sheds-light-on-ashkenazi-jewish-genome-and-ancestry" rel="nofollow">https:&#x2F;&#x2F;systemsbiology.columbia.edu&#x2F;news&#x2F;study-sheds-light-o...</a>

Is it a genetic bottleneck, or is it &quot;We&#x27;d rather not understand Jewish DNA so much?&quot;