Why would you think 'Jewish biologists' denounced the study?
This is a continuing story and widely publicized, and a wildly popular subject in the Jewish world. see the work of orthodox Rabbi Yaakov Kleiman, for example.
A good collection of resources is found at:
http://tarkus.pha.jhu.edu/~ethan/jFAQ.html
see also
http://www.aish.com/societyWork/sciencenature/Abrahams_Chromosomes$.asp
http://www.aish.com/societywork/sciencenature/Jewish_Genes.asp
These [widely scattered] Jewish communities are more closely related to each other and to other Middle Eastern Semitic populations -- Palestinians, Syrians, and Druze -- than to their neighboring non-Jewish populations in the Diaspora.
http://www.khazaria.com/genetics/abstracts.html
At the present time, it is known that Eastern European Jews have a significant Eastern Mediterranean element which manifests itself in a close relationship with Kurdish, Armenian, Palestinian Arab, Lebanese, Syrian, and Anatolian Turkish peoples.
http://www.haaretzdaily.com/hasen/pages/ShArt.jhtml?itemNo=96990
http://www.judaism.com/display.asp?type=newbook&etn=BCBEG
http://www.jewishsf.com/bk010309/sbaychrom.shtml
"I will never truly understand how people can get to the point where thinking like this takes place."
What would give you the impression that they were "thinking" about anything?