Usually when I see reviews or comments about the various ancestry location predictors, the focus is on one person -- usually the author. Rarely do we look at whole families. Below are the myOrigins predictions for a family of 4. Such an analysis offers more constraints than those that look only at one person at a time. However, that narrower focus may be a good place to start.
Most of you probably know that myOrigins is a new feature being rolled out by FTDNA to replace its now primitive Population Finder. It offers many more than the previous 4 possible populations of origin. It also gives users the chance to review the predicted ancestral distribution for those who are Family Finder matches on their atDNA.
This kind of prediction is far from settled science. There is nothing wrong with the genetic analysis of reputable labs. However, it is easy for sensation seekers to make unsupportable claims. The problems are that we often are not told when it was that our ancestors were supposed to have lived in the predicted locations and also that our ancestors were quite mobile -- at least in certain periods. For example Geno 2.0 tries to predict where our ancestors may have been thousands of years ago. Other tests aim just a few hundred years back in time. Much as we would love to know in which postal zone our ancestors lived in during a particular decade, DNA analysis alone is far from unlocking such pinpoint information.
If the DNA is trying to place us even 15 to 20 generations back in time, none of us have any clue who all or even most of our ancestors might have been. The most diligent among us may have information about a small percentage of our forebears that far back.
This is not to say that information from tests like myOrigins is not fascinating and sometimes informative. However, we need to resist the temptation to swallow it whole. We need to digest it carefully and need to correlate it with information from other sources.
In examining the family of four below, it is important to remember that we are examining a known family unit. These are not 4 genetically independent individuals. The general findings for each parent are not inconsistent with what is known about their ancestral origins from other sources. This level of analysis is at best two dimensional. It begins to get more interesting when each family member is compared with each other family member.
If we can assume that the predicted information about the parents are generally in a range close to the truth, the predicted information for the children begin to raise some questions. We all know that atDNA is random and that two siblings generally inherit about 50% of the same segment. That could account for some of the variation between the daughter and the son.
The values for each child would be expected to be within or near the ranges established by the two parents. If the assumption made in the last sentence is accepted, most of the values for the daughter are not unexpected although her European Coastal Islands component is more than 10% higher than that for either parent. Other than the small Trans-Ural Peneplain result, nothing else about the daughter's results seem to stand out on the face of them.
The son is a different matter. His much lower European Coastal Island component than any other family member and his European Northlands component of more double any other family member strain credibility that they resulted from just random atDNA inheritance in only a single. All this might be statistically possible but it strains credibility.
myOrigins for a family of 4
Father
|
Mother
|
Daughter
|
Son
|
|
European Coastal Islands
|
58%
|
67%
|
76%
|
35%
|
European Northlands
|
15%
|
18%
|
19%
|
45%
|
European Coastal Plain
|
13%
|
12%
|
||
North Mediterranean Basin
|
22%
|
2%
|
2%
|
6%
|
North
Circupolar
|
5%
|
|||
North African Coastlands
|
2%
|
|||
Trans-Ural
Peneplain
|
4%
|
It is not my intention to single out myOrigins for a greater levels of scrutiny than we apply to other similar tests. We should be applying them to all such test results. As drawn to these predictions as we are, do we believe they are as ready for prime time as genetic genealogical tools in the way that other DNA tests have become?
You may want to tune in to Elise Friedman's webinar on Monday at high noon Houston time for more details about the launch of this new product.
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