As I'm going through Genome Mate Pro adding named segments to my segment map this week the differences in the size of the segments between my mother and I were so apparent. Many of the segments I share with matches are less than 20 cM's. My mother has many more segments over 20 cM's, and many over 30 cM's. She was born in 1921, whereas I was born in 1963. As the generations pass our genetic links to our immigrant and early American ancestors will not be visible in our DNA. Definitely test all older relatives first.
I've been mapping my segments in Genome Mate Pro. My main focus right now is on the segments shared on chromosomes 5 and 18 which relate to possible Campbell family matches. Since the only thing I know about Campbell is I have an ancestor named Sarah Campbell who married Anderson Wray in Jackson County, Indiana, possibly born in Tennessee, that's everything I know. I updated the GEDmatch data with new matches. I've been going through these segments and naming them if I can determine the ancestors they came from. This process involves using Ancestry trees. Also Googling names and email addresses to see if there is a family website.
Gedmatch is estimating the length of the segments as longer than AncestryDNA. I've filled in more of chromosome 18 adding matches besides the Campbell match. Two tested with Ancestry and overlap each other, but neither appear as shared matches. According to AncestryDNA one of these matches shares one 14.4 cM segment. GEDmatch estimates the segment is 22.4 cMs. The other match is said to share 1 segment of 12.7 cM's. According to GEDmatch the segment length is more than twice that length at 28.3 cM's. Since Ancestry doesn't share segment data there is no way to know whether their segments overlap, according to their calculations. They do overlap according to GEDmatch.
Examining the family trees of theses matches I find that the two matches segments I've added to chromosome 18 might share more than one set of ancestors with me. These two added matches share the surnames Campbell and Wray with us. My ancestors Anderson Wray and Sarah Campbell married in 1833. On first examination it could be that these matches are also their descendants, but they aren't. Instead they are descendants of Anderson Wray's grandfather Benjamin Wray and his second wife Patsy Goode. The Campbells they descend from didn't live in Franklin County, Virginia where the Wray family lived.
What is particularly interesting about the match at Family Tree DNA is they have ancestors who lived in Iola, Kansas. Iola is a very small town. Anderson Wray migrated with some of his children to that town. He died there. According to this match she doesn't have any relationship to the Wray family? Either this is a coincidence or there was a non paternity event? If this segment on chromosome 18 came down from Benjamin Wray then an NPE is likely. On the other hand if the match relates on the Campbell line then her tree is correct.
Last week I discovered one particularly interesting Campbell matches ancestors were from Greene County, Tennessee. Sarah Campbell-Wray was said to have been born in Tennessee. The recently added matches, who tested at AncestryDNA, have Campbell ancestors from Lee County, Virginia and Hawkins County, Tennessee. All of these places are close together in Northeast Tennessee and Southwest Virginia. My tendency is to think these segments are related to Wray and not Campbell because both share Wray ancestors?
Looking at chromosome 18 at Genome Mate Pro, after marking all of these segments, it's impossible to see where segments begin and end.
Charting the segments with Kitty's Segment Mapper we see exactly how they fit together (chart below). Not sure why there is an overlap of the blue at Genome Mate Pro? This view is very helpful. We see the Campbell match I am most interested in with segments bookending the others. I found another match who shares one of the exact segments with her. This matches has a very small tree containing no Campbell's or Wray's.
Based on this view my mother either inherited one long segment of DNA from her Great-Great Grandfather Anderson Wray, or chromosome 18 is mix from both Anderson Wray and Sarah Campbell? The book ending may suggest there is a mix of Wray and Campbell DNA on chr. 18? The Campbell match of special interest at AncestryDNA, the booking ending match, has a fairly complete tree out to around 6 and 7 generations with no Wray's on it?
The shared matches feature at Ancestry didn't give me a clue that 3 matches had something in common, facts important to me were hidden. It would have been helpful to know they share either overlapping segments, or segments that are close together. None of these matches appear to match each other even though two descend from Benjamin Wray and Patsy Goode, and both tested at AncestryDNA? They don't show up as shared matches? They do match at GEDmatch.
Doing this analysis required quite a bit of time. No one site has everything needed to effectively analyze and compare matches. I had to go back and forth between Ancestry, Family Tree DNA, 23andMe, GEDmatch, Genome Mate Pro, and Kitty's Segment Mapper. 23andMe has to best tools, but no trees. If they would add a tree feature I would recommend everyone test there.
I will continue to work with the matches on chromosome 18. I do have many more matches I need to evaluate. This kind of analysis is only possible if you have segment data. This analysis is necessary if you are comparing with distant cousins.
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