Geographical Connections Through GEDmatch Admixture Analysis

Updated September 18, 2011

Today GEDmatch added a new utility for analysing individuals complete DNA file and coming up with an admixture breakdown by geographical region. I had the utility analyse my data and it produced the columns below.

I wondered what it might say about Frank so I decided to subtract my known western European DNA (mother=50%; paternal grandmother=25%) from the western European total and distribute the difference proportionally across the rest of the percentages. I also decided to try it with taking out 100% of western European DNA to simulate 100% of it coming from the two women. However, it is worth noting the discrepancy between the 75% of DNA contributed by those 3 grandparents is far larger than the 44.9% Western Europe DNA turned up in the analysis. Since we don’t have either DNA analysis or genealogical information on them to use to make a decision about further data extractions, I just left that 30% in.

This discrepancy raises a question however. Theoretically, the total western European DNA credited to Molly and Dory should total almost exactly 75%. However, the analysis only shows 44.9%. What happened to that other 30%? The only explanation that I can think of is that either Molly or Dory or both had some DNA from non-Western European sources. That would be news to me. However, Brian suddenly remembered a conversation with Dory in which she mentioned that her father had mentioned the possibility of some Moroccan ancestry! We have not had time to talk abut that further. In the meantime I am trying to contact Dory’s cousin Tony in Oakville to see if he knows anything or knows if any family members have had DNA testing done. Also, I’m going to contact Bryce, Jeannine and Dennis Sharpe to see if they can shed any light on an Italian connection to the family that his mother, Molly’s half-sister may have mentioned. There was something about a ship building, which was her father’s business.

The distribution over the regions is interesting on its own. However, the adjustment to the western Europe DNA produces fascinating results. After extracting Western Europe, in a gross consolidation the Mediterranean and the West Asian (Arabian Peninsula) added together to total 55%. If you also add SouthWest Asia that total climbs to 62%. Eastern Europe is 30%. The residual 8% is Asian or African.

West Asia includes Saudi Arabia, Israel, Jordan, Lebanon, Syria, Iraq, part of Iran and Turkey as well as smaller countries.

If you want a visual definition of West Asia and the other Asian sectors see the colour map at http://en.wikipedia.org/wiki/Geography_of_Asia

For the time being, we don’t have an explanation for the Eastern European contribution, but it % size would suggest that it is a relatively recent contribution. The original 29.6% would suggest that either of Frank’s parents could have made that contribution but it is unlikely that that great-grandparent would have 100% Eastern European DNA.

GEDmatch Admixture Analysis of Ian McCallum
9/3/2011
**Adjustment by Subtracting Obvious Western European DNA
Mother DNA % 50%
Grandmother DNA % 25%

Removing 100% of Western Europe
New Weighting
Population Self Added
East_European 29.6%
West_European (removed 44.9%)
Mediterranean 44%
Neo_African 0.2%
West_Asian 11.3%
South_Asian 2.3%
Northeast_Asian 1.0%
Southeast_Asian 0.7%
East_African 0.5%
Southwest_Asian 6.7%
Northwest_African 3.5%
Palaeo_African 0.4%
100%

Adjusted Summaries
East_European 30%
Mediterranean+West Asian (Arabian Penninsula – Lebanon, Israel, Jordan, Syria, Iraq, Saudi, Yemen etc) 55%

Note: also read the 23andMe Ancestry Lab posting under Category DNA or Semitics. It is a breakdown of the DNA that is shared with Ashkenazim.

Ian

1 Comment »

  1. Gale Said,

    November 23, 2012 @ 12:01 AM

    I have a DNA match at gedmatch.com com with(Mizya Blyakher)and I am responding to her post on Grandfather Frank McCallum – Who Was He Really? I am Jewish and would like to correspond with her. We are sharing dna through the X chromosome.

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