Testing for relationships #dna


Dr. Richard Pavelle <rp@...>
 

A person who I believe to a 4th blood cousin and I wish to determine
whether we are, in fact, related. What kinds of tests would determine
that and what is the cost.

Thanks.

Researching: GODT, DERFLER, TURER, ENTENBERG

Dr. Richard Pavelle


A. J. Levin <aj_levin@...>
 

There's actually a _very good_ chance 4th cousins will have nothing
passed down in common: "even money," as the bettors say.

http://www.familytreedna.com/faq/answers/default.aspx?faqid=17#628

For example, my mother's third cousin once removed shares a block of
16.5 centimorgans with her, which by sheer chance I did not inherit,
so I have zero sharing with my fourth cousin. Based on other natches
it appears we both inherited DNA >from our common ancestors, just not
the same ones.

Best,

A.J. Levin

--- On Fri, 4/22/11, sachs@... <sachs@...> wrote:

there is also a very small chance that you are truly
4th cousins but your DNA would have nothing in common
since randomly only half of DNA of a
parent is passed down to each of their children.


rayvenna@...
 

Has anyone done a comparison of the new FamilyFinder results (they
recently changed their methodology) and known relationships? I had my
second cousin twice removed tested and the FamilyFinder test correctly
pegged him as a second cousin. One example isn't nearly enough to
tell how accurate these results are, however, and I haven't found
paper trails for any of the other DNA matches. Has anyone else had
similar experiences where the FF correctly pegged the relationship
with a known cousin?

Thanks,
Mindie Kaplan
Gaithersburg, Maryland


Judy Simon
 

For myself: an aunt was correctly predicted; a 1st cousin once
removed was predicted to be a 2nd cousin
For my husband: a 1st cousin was correctly predicted; a 1st cousin
once removed was predicted to be a 1st cousin.

Judy Simon
Stony Brook, NY
researching BROZGOL, KAPELUSHNIK, MIRANSKI, SKUTELSKI, BAILENSON,
RAPPAPORT, PASSMAN >from Rezekne, Daugavpils and Ludza, Latvia;
LEFKOWITZ, KELMER, OLSTEIN, MEZELSOR, CHOJNA, AKERMAN, PLANCZNER from
the Lodz area, Poland

On Fri, Apr 22, 2011 at 4:32 PM, <rayvenna@...> wrote:

Has anyone done a comparison of the new FamilyFinder results (they
recently changed their methodology) and known relationships? I had my
second cousin twice removed tested and the FamilyFinder test correctly
pegged him as a second cousin. One example isn't nearly enough to tell
how accurate these results are, however, and I haven't found paper
trails for any of the other DNA matches. Has anyone else had similar
experiences where the FF correctly pegged the relationship with a known
cousin?


Arline and Sidney Sachs
 

Dr. Richard Pavelle <rp@...> wrote "A person who I believe to a
4th blood cousin and I wish to determine whether we are, in fact, related.
What kinds of tests would determine that and what is the cost."

First, since Family Tree DNA (FTDNA) has the largest database, that is the
company to use because you would most likely find additional matches. If
both of your lines are paternals and you both are males, you should use
the Y-DNA test. If both lines are on the maternal lines, then use and the
mtDNA test. However, either test would not tell you if you do match which
level of cousin you are. If you two couse on any family lines, then you
can use autosomal tests (Family Finder at FTDNA). It would give an
estimate how close you are related.

However if you are both Ashkenazic Jews, because of centuries of
in-blooding, presently the autosomal test would give you so many match
results. You really can not tell whether the common relative was the one
5 generations back you are looking for or combination of two or more
relatives of 6 or more generations further back. In the same way, if you
are truly 4th cousin, the test may estimate you as closer cousins. Beside
this, there is also a very small chance that you are truly 4th cousins but
your DNA would have nothing in common since randomly only half of DNA of a
parent is passed down to each of their children.

Sidney Sachs
Lorton, VA


Judy Simon
 

On Sat, Apr 23, 2011 at 11:58 AM, Janet Akaha <Akaha@...> wrote:
My brother did Family Finder initially after convincing a likely but not
confirmed relative to also do Family Finder. Our likely relative is a
PERLZWEIG, and my grandmother was also a PERLZWEIG. Family finder has
pegged us as 4th cousins and our largest block is 14.73 cM on the 16th
chromosomes. Now *if* we can assume that this block came >from a common
PERLZWEIG ancestor, wouldn't it also follow that anyone who also overlaps us
at this exact location would also share that same ancestor?
Not necessarily. Each chromosome segment consists of material you
inherited >from your mother and your father. When someone matches you
on that segment, they are technically "half-identical" and hence, some
of us refer to matching segments as "half-identical" regions. Two
people can "share" the same segment with you, but they might not share
it with each other. Before you can conclude that two people who share
the same segment with you all have the same common ancestor, you must
first find out if they share that segment with each other. It could
happen that one of them is half-identical with you on the part you
inherited >from your father, and the other is half-identical with you
on the part you inherited >from your mother. On any given segment, if
each of them matches you *and* they match each other, then all three
of you have a common ancestor >from which you inherited that particular
segment.

Judy Simon
Stony Brook, NY
researching BROZGOL, KAPELUSHNIK, MIRANSKI, SKUTELSKI, BAILENSON,
RAPPAPORT, PASSMAN >from Latvia; LEFKOWITZ, KELMER, OLSTEIN, MEZELSOR,
CHOJNA, AKERMAN, PLANCZNER >from the Lodz area, Poland


Janet Akaha <Akaha@...>
 

My brother did Family Finder initially after convincing a likely but
not confirmed relative to also do Family Finder. Our likely relative
is a PERLZWEIG, and my grandmother was also a PERLZWEIG. Family
finder has pegged us as 4th cousins and our largest block is 14.73 cM
on the 16th chromosomes. Now *if* we can assume that this block came
from a common PERLZWEIG ancestor, wouldn't it also follow that anyone
who also overlaps us at this exact location would also share that same
ancestor? I went through "chromosome browser" and checked out all my
close to immediate matches. There were 4 other people. Three of them
shared slightly larger chunks of dna at this same location.

My mother wasn't Jewish. So I do find that I have many fewer matches
than most of my other matches (as my results show much less
amplification due to multiple relationships). However, one of the
men I wrote to ask if any of our PERLZWEIG story made any sense, wrote
back to say that he has a PERLES/PERLESS ancestor >from the same
general area. He has been unable to find additional information prior
to their arrival in the US. (On my family tree the name PERLZWEIG
has been changed to PERL, PEARL, PEREY, PEEL etc., so Perles isn't a
stretch).

Based on the fact that two different unconfirmed relatives match me at
this location *and* we have a surname and geographic tie as well, isn't
it safe to assume that *everyone* who matches me here is a PERLZWEIG
cousin?

Janet Billstein Akaha (my brother Robert Billstein did the DNA)
Salinas, California