In addition to written family trees, I am surprised that more use is
not made of Y-DNA testing in establishing connections along the male
line of these rabbinic families.
I am the administrator of the Heimlich Y-DNA project (through Family
Tree DNA), and we were surprised to find that the surname had three
separate and distinct genetic male ancestors (each of a different
haplogroup). Of the fifteen branches we have tested so far, everyone
falls into one of the three.
Leslie Reich <firstname.lastname@example.org> of Manchester wrote:
There exist no genuine ancestral charts showing relationships between
people alive today and those of Talmudic times, over 1500 years ago.
(Those who claim descendancy >from the Tanna, Rabbi Yochanan
Hasandler, who lived around 150 C.E., are unable to show the linkage.