It is pretty clear that many Jews are related, especially those in the Cohen(priests) and Cantor(temple assistants & singers) casts that at one time were restricted only to marry among themselves. Those in the Israel caste (commoners) tend to be more diverse, especially in Russia.
There was a Turkic tribe called the Kazars that seems to have converted to Judaism when they found themselves caught between the Russian Christians and the Ottoman Moslems. Apparently, most were members of the Israel caste.
There is no doubt that Jews are often closely related. The issue is are they so different they can be called a RACE?
Most anthropologists don't seem to think so. Judaism has alwqays pondered the question "What is a Jew?"
If it is a belief, there is a huge difference between the Ultra Orthodox and nonpracticing atheists.
If it is a race, there are huge genetic differences between Falashi Ethiopian Jews, Russian Jews, Sephardic Jews and Yemeni Jews.
The only thing that is generally agreed upon is that if one's mother is Jewish, then one is Jewish.
Indeed is the term RACE relevant, given what we know about genetics today?
There are not many similarities other than skin color between Australian aborigines, The San Bushmen of the Kalahari, and the Bantu groups of central Africa.