Monday, September 1, 2014

The Other Melungeon DNA Project

Yates Profile of Melungeons

"In 2010, Donald Yates self-published a paper entitled "Toward a Genetic Profile of Melungeons in Southern Appalachia" on his website. The paper was not subject to academic scrutiny or peer review. For analysis, Yates used a tool based on OmniPop which uses as input the 21 CODIS autosomal markers.

The original OmniPop tool was designed by Brian Burritt of the San Diego Police Department as a tool created to differentiate between people, specifically to determine their primary race, not to compare them for similarities. He created the OmniPop spreadsheet from 225 police and forensic articles that had been published and referenced Codis marker information about people from specific populations. How these populations were identified, how the individuals were identified as members of that particular population, and by who are all questions that remain unanswered and probably vary depending on the article and situation in question.Furthermore, a normalized distribution of the world populations is not represented in OmniPop.

The output of the database, population matches, is dependent solely on the distribution of the populations input and which of the 21 marker values are selected to be utilized in the analysis.

Burritt’s commentary regarding genealogists using OmniPop for genealogical ethnicity comparisons is that they were using a tool not created for this purpose and were over-analyzing the results.
Yates uses the OmniPop derived tool to evaluate and report on the results of "40 self-identified Melungeon descendants" and reports on "the probabilistic predictive results of Melungeon ethnicity."

Yates states that, "Of the participants, 21 were born in eastern Tennessee or adjacent states. The birth location of about 20% were unknown. Nine came from a single extended family. There were 11 siblings and 11 parent-child pairings. Many not closely related were distantly connected. Surnames were consistent with a list published by Kennedy and included Adams, Barnett, Caldwell, Carter, Collins, Cooper, Douglas, Elliott, Goode, Goodman, Goins, Hall, Jones, Kennedy, Mize, Ramey, Sparks, Starnes and Stewart. Of these surnames, only Goins, Goodman and Collins are included in the Core Melungeon grouping and of those in Yates study, it is unknown if they have a genealogical connection to the Hawkins/Hancock County families. Genealogical and/or relationship information was not provided.

Yates reports that his population group showed notable levels of Jewish, both Ashkenazi and Sephardic, Middle Eastern, Native American, African and Iberian ancestry. In summary, Yates concludes that the Melungeons are not primarily drawn from ancestries in northwest Europe but represent an amalgam of Mediterranean, Middle Eastern, North African, African and Native American ethnic groups. He further states that the Melungeon founders were probably neither British nor Christian and that the "Arab and Turkish-descended Melungeons probably shared Muslim traditions" in addition to "Sephardic and Ashkenazic" religious practices.

When compared to other autosomal analysis tools and when compared with a known genealogical pedigree chart of the testee, OmniPop has proven deficient as a reliable measure of ethnicity.

In the paper, Revealing American Indian and Minority Heritage Using Y-line, Mitochondrial, Autosomal and X-Chromosomal Testing Data Combined with Pedigree Analysis, the author analyses various ways to interpret CODIS marker results using OmniPop and provides a comparison of OmniPop's reliability for an individual whose ethnicity is known and proven using a pedigree analysis methodology. For an individual with 23% proven German heritage, 22% proven British Isles heritage and 14% proven Dutch heritage, OmniPop reported Caucasian as the most common element, followed by Poland, Belgium, Mexico, Spain, Michigan Native American, Indian, Serbian and Norwegian. No British Isles results were listed, as British Isles locations are not contained in the OmniPop reference data base, nor did results include Germany or the Netherlands. This discrepancy is problematic and certainly raises questions as to the reliability of OmniPop based results. It is interesting to note that OmniPop, when applied as intended by Brian Burritt, to identify primary race, as opposed to identifying minority admixture, was correct. Most individuals can readily identify their primary race without using OmniPop, but in a police environment, it would be a very valuable tool.

It would certainly be easy to inadvertently skew the resulting matches to be heavily in favor of a specific population if articles dealing with reference samples of that particular population were included disproportionately in the reference data base.

The high level of interrelatedness within the test population of Yates study raises other concerns as well as the variety of family surnames included. Yates used Kennedy's expanded surname list.

Also of concern are the participants' "self-identification" as Melungeon. As the administrators of the Melungeon-Core (Y-line), mtDNA and Family DNA projects, we receive daily e-mails from people who have found Melungeon information on the internet and have "self-identified" as a member of that population based on a wide spectrum of erroneous information. Self-identification may be a criteria for consideration, but it is not a selection criteria for inclusion.”

From: "Melungeons,A Multiethnic Population

Disclosure: I am NOT endorsing Donald Yates or DNAConsultants, the opposite, I wouldn't touch either with a 12 ft. vaccinated pole. Cretinitis can be contagious..... 


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