Dear John, I would definitely try to get your aunt to test. If your aunt has a child, I would also test them. I would suggest caution about situations where you share 14 matching segments, but where all of the matching segments are short (in this case all less than or equal to 7.7 cMs). A significant majority of matches under 5 cMs are going to be IBS. I came to this conclusion early on after looking at the Family Finder data and also at the data from the 23andMe Mennonite project at http://kquilting.homeserver.com/23andme/resultsLoGerman.html where we use a 4 cM threshold for matches. If you look at my dad's (Robert Janzen) file on that web site you will see quite a few matches for him that are in the 4-6 cM range that are from people who aren't of Mennonite ancestry. As far as I can tell, essentially all of my dad's ancestors were Mennonites in Poland or that region in 1700. However, all of the people below row 725 have no Low German Mennonite ancestry from Poland. A few of those people do have Polish ancestry, but if there is a genealogical connection with any of the match! es on rows 726 to 934 the genealogical connections are likely to be before 1700. I would suggest you wait until you get your results from your two children back before you look at this situation again. At that point compare your children to this person as well and then see how many of the 14 segments that they match on. Also keep in mind that the total number of SNPs in the matching segment is another important clue as to whether or not the segment will be IBD or not. If the number of SNPs is over 1000 it is much more likely to be IBD than if the number of SNPs in the segment is 500 or less. If you look at my dad's file I mentioned above you will note that many of my dad's matches in the 4-6 cM range below row 725 have only 250-600 or so SNPs in the matching segment. This significantly increases the probability that the matching segment will be IBS. Sincerely, Tim Janzen -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of John F Smeltzer Sent: Saturday, January 07, 2012 11:30 AM To: [email protected] Subject: Re: [AUTOSOMAL-DNA] SUBJECT: How do you work a 5 way FF match with few clues ? Thanks Tim ... I understand your response to my first question. And I appreciate the clarity very much. My brother has no children. I have two children who will both test. My mother is no longer living BUT she does have a sister who MAY be willing to test. That should help. And, I have her 1/2 brother testing as we speak. So....I'll backdoor the phasing as best I can with a host of testing .... that works for me but is clearly impractical for most I'm quite certain . On my second question I understand the single segment issue of IBS vs IBD. But .... what about the situation re: IBS v. IBD where you and one other person share 14 matching segments ranging in size from 2.5 to 7.7 cM. Now, any ONE of those segments ... maybe even 50% or more of those segments could be IBS .... but surely in a group of 14 seemingly matching segments ... even those coming in below the threshhold that causes us to all go .... "I don't think so" ..... there is a true IBD match. Now ... we may not be able to find the connection via paper trail but doesn't such a complex match situation (multiple matching segments ... in my example 14) pretty much guarantee a biological IBD tie somewhere in that mixture? John