Peter I think your statement is correct, and true virtually all of the time. It's an excellent way to set up the draft of your chromosome map. I've now found over 200 Common Ancestors that go with specific segments. This does not include about 30 Common Ancestors I've had to set aside as additional info proves they cannot be correct (they ARE Common Ancestors, they just didn't provide the DNA segment my Match(es) and I share. None of our segments, phased or not, should be locked in until at least one more overlapping segment turns up. And no Common Ancestor should be locked down until at least 1-2 more Matches on that segment can agree on the Common Ancestor. These kind of shifts and confirmations are far more frequent than the very rare chance of an A=B=C=A situation not being Triangulation. At least in my case the score is 30-0. Phasing merely divides the problem into two parts: paternal and maternal. You still have to find the Common Ancestor. The Triangulation process (no phasing required) can divide overlapping shared segments into three groups: two real groups and IBS. All you need is one parent, aunt/uncle, or known cousin to match one of the two real groups to be able to assign them both to the appropriate parent's side. I've been able to assign over 80% of my genome without phasing. This is roughly what Tim has done with phasing. At the end of the day - it's all about determining the Common Ancestors for segments (and confirming them). Jim - Sent from my iPhone - FaceTime! On Nov 18, 2013, at 1:20 PM, peterebay@yahoo.com wrote: > Hello Steven, > > If Alfred matches Betty on a 7cM or greater segment of chromosome 4 and Alfred matches Charles on a 7cM or greater segment of chromosome 4 (which overlaps the Alfred/Betty segment) and Betty matches Charles on this same >=7cM segment, then I believe this almost definitely confirms (or confirms) they all received that segment from a shared ancestor. No phasing is necessary. > > I understand they each have two copies of chromosome 4. > > I would like to hear from anyone as to why the above statement is wrong. > > Thank you and sincerely, Peter > > Peter J. Roberts > > > Re: [AUTOSOMAL-DNA] Finding shared atDNA ancestry without phasing > Date: Mon, 18 Nov 2013 08:55:29 -0500 > References: <1384781334.49601.YahooMailNeo@web160806.mail.bf1.yahoo.com> > In-Reply-To: <1384781334.49601.YahooMailNeo@web160806.mail.bf1.yahoo.com> > > > Peter: > > All FTDNA tells you is that there is a match on strand A or strand B at a > certain location. Unless you phase the genomes you do not know if they all > match on strand A or strand B or a combination of the two. > > Steven > > > > On Mon, Nov 18, 2013 at 8:28 AM, Peter J. Roberts <peterebay@yahoo.com>wrote: > >> Hello Kethy, >> >> I believe we can skip phasing in situations where three or more people >> share the same segment and ALL match each other on that overlapping/shared >> segment. >> >> Sincerely, Peter >> >> Peter J. Roberts > > ****Please include this message in any replies**** > > > ______________________________ > For answers to Frequently Asked Questions about mailing lists, please see: > http://dgmweb.net/MailingListFAQs.html > > > ------------------------------- > To unsubscribe from the list, please send an email to AUTOSOMAL-DNA-request@rootsweb.com with the word 'unsubscribe' without the quotes in the subject and the body of the message