Sally Bruckheimer <sallybru@...>
In 1000 years, you have many, many Nth great grandparents - more than there
were Jews in Western Europe. We see that in the prevalence of certain
genetic diseases which are amazingly prevalent in the Ashkenazi Jews. We
see that in DNA research. And this is based in theory as well, as we have
talked about on Jewishgen several times before.
The fact is, Ashkenazi Jews are probably all descended >from Rashi if any one
of us is. Perhaps the Jaffe family remembers the family descent that many
others don't. But that is the problem with much of DNA used for genealogy
purposes; if you aren't fourth cousins to someone that you think you might
be related, the DNA tests can tell you whether your father's father's
father's...father or mother's mother' mother's...mother was or was not the
same, but there are other ancestors of the same degree. If the DNA test for
your paternal line say you aren't fifth cousins with somebody, that does not
mean you aren't related in another line, or that you are not sixth or
What happens is this: On my Sephardic line, I found who I thought was a
20th cousin! Amazing, here was somebody who had my same ancestor who lived
in 1600! We traded Gedcom files, and, surprise, we are 5th cousins in
Among the Sephardi, it is much easier to trace distant cousins because they
had family names much earlier, and in some places the records are very good.
But that doesn't mean that genetics and relationships work differently in
the Sephardi than in the Ashkenazi. I always write and tell somebody that
is thinking about a DNA test to see if another person of the X family >from a
certain area is really related: "If you aren't 4th cousins in the
all-paternal line (where the surname was handed down), you are certainly 5th
or so cousins and cousins in other lines. If a person wants to do a DNA
test, I think that they should know that a negative result doesn't exclude
much, simply one ancestral line to some degree.
In Rashi's case, there is no chance to test your father's father's father's
line, as Rashi had no sons. You might test to see if your mother's mother's
mother's...line is related by Rashi's wife (assuming there was only one,
which might well not be true). And that would be only the all-maternal line
that was tested.