[LINK] Two GNXP links on hidden ancestries
Jun. 6th, 2012 04:53 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
rfmcdonaldGNXP's Razib Khan posted two links to studies of isolated populations with claims to unexpected ethnic origins some time ago. The first determined that two Hispanic populations which lay claim to Jewish ancestry, one in Ecuador and one in the American state of Colorado, actually did show evidence of Jewish ancestry.
The second focused on the Melungeons, a population group in Appalachia that most recently has laid claim to Turkish or Middle Eastern ancestry. A study of select families indicates that, in fact, the non-white ancestry in question was sub-Saharan Africa, perhaps the consequence of interracial marriage and relationships in the very early period of American settlement.
Given the racial hierarchies of the early 21st century world, it's probably not surprising that Jewish ancestry among these two Hispanic groups is now held as a source of pride--I've read anecdotal reports of many of the American Hispanics converting to Judaism--while the African ancestry is a matter of controversy. (One commenter at the second GNXP post almost seems to imply that there couldn't be any African ancestry among Mulungeons generally since the women were so pretty. Am I reading this wrong, please?)
Modern day Latin America resulted from the encounter of Europeans with the indigenous peoples of the Americas in 1492, followed by waves of migration from Europe and Africa. As a result, the genomic structure of present day Latin Americans was determined both by the genetic structure of the founding populations and the numbers of migrants from these different populations. Here, we analyzed DNA collected from two well-established communities in Colorado (33 unrelated individuals) and Ecuador (20 unrelated individuals) with a measurable prevalence of the BRCA1 c.185delAG and the GHR c.E180 mutations, respectively, using Affymetrix Genome-wide Human SNP 6.0 arrays to identify their ancestry. These mutations are thought to have been brought to these communities by Sephardic Jewish progenitors. Principal component analysis and clustering methods were employed to determine the genome-wide patterns of continental ancestry within both populations using single nucleotide polymorphisms, complemented by determination of Y-chromosomal and mitochondrial DNA haplotypes. When examining the presumed European component of these two communities, we demonstrate enrichment for Sephardic Jewish ancestry not only for these mutations, but also for other segments as well. Although comparison of both groups to a reference Hispanic/Latino population of Mexicans demonstrated proximity and similarity to other modern day communities derived from a European and Native American two-way admixture, identity-by-descent and Y-chromosome mapping demonstrated signatures of Sephardim in both communities. These findings are consistent with historical accounts of Jewish migration from the realms that comprise modern Spain and Portugal during the Age of Discovery. More importantly, they provide a rationale for the occurrence of mutations typically associated with the Jewish Diaspora in Latin American communities.
The second focused on the Melungeons, a population group in Appalachia that most recently has laid claim to Turkish or Middle Eastern ancestry. A study of select families indicates that, in fact, the non-white ancestry in question was sub-Saharan Africa, perhaps the consequence of interracial marriage and relationships in the very early period of American settlement.
The Melungeons were a group of individuals found primarily in Hawkins and Hancock Counties of Tennessee and in the far southern portion of Lee County, Virginia which borders Hawkins and Hancock counties in Tennessee. At one time isolated geographically on and near Newman's Ridge and socially due to their dark countenance, they were known to their neighbors as Melungeons, a term applied as an epithet or in a pejorative manner.
As the stigma of a mixed racial heritage dimmed in the late 20th century and was replaced by a sense of pride, interest in the genealogy and history of the Melungeon people was born. With the advent of the internet and popular press, the story of these people has become larger than life, with their ancestors being attributed to a myriad of exotic sources: Sir Walter Raleigh's Lost Colony, Ottoman Turks, The Lost Tribes of Israel, Jews, Gypsies, descendants of Prince Madoc of Wales, Indians, escaped slaves, Portuguese, Sir Francis Drake's rescued Caribbean Indians and Moorish slaves, Juan Pardo's expedition, De Soto's expedition, abandoned pirates and Black Dutch, among others. Melungeon families themselves claimed to be Indian, white and Portuguese.
Furthermore, as having Melungeon heritage became desirable and exotic, the range of where these people were reportedly found has expanded to include nearly every state south of New England and east of the Mississippi, and in the words of Dr. Virginia DeMarce, Melungeon history has been erroneously expanded to provide "an exotic ancestry...that sweeps in virtually every olive, ruddy and brown-tinged ethnicity known or alleged to have appeared anywhere in the pre-Civil War Southeastern United States."
Given the racial hierarchies of the early 21st century world, it's probably not surprising that Jewish ancestry among these two Hispanic groups is now held as a source of pride--I've read anecdotal reports of many of the American Hispanics converting to Judaism--while the African ancestry is a matter of controversy. (One commenter at the second GNXP post almost seems to imply that there couldn't be any African ancestry among Mulungeons generally since the women were so pretty. Am I reading this wrong, please?)
