Category Archive 'Genetics'
22 Jan 2013
90% of living Jews are European (Askenazi) Jews. There are two theories of the origin of European Jewry: the Rhineland Hypothesis contends that European Jews fled Palestine after the Roman destruction of the Temple in 70 A.D. or after the Muslim conquest of Palestine in 637 A.D., migrated into Europe via Italy and Spain, then settled along the Rhine, before being driven eastward by persecution. The use of Yiddish, a High German dialect, by Ashkenazi Jews provides substantive support for their origin somewhere in Germany.
The alternative Khazar Hypothesis, popularized by Arthur Koestler, argues that nearly all European Jews really descend from the Khazars, a Turkish-speaking people, who converted to Judaism en masse in the 8th century.
New genetic evidence produced by a study by Geneticist Eran Elhaik of the Johns Hopkins School of Public Health in Baltimore, published in the British journal Genome Biology and Evolution, on The Missing Link of Jewish European Ancestry: Contrasting the Rhineland and the Khazarian Hypotheses provides strong support for the Khazar Hypothesis.
Thus far… the Khazars’ contribution has been estimated only empirically, as the absence of genome-wide data from Caucasus populations precluded testing the Khazarian hypothesis. Recent sequencing of modern Caucasus populations prompted us to revisit the Khazarian hypothesis and compare it with the Rhineland hypothesis. We applied a wide range of population genetic analyses to compare these two hypotheses. Our findings support the Khazarian hypothesis and portray the European Jewish genome as a mosaic of Near Eastern-Caucasus, European, and Semitic ancestries, thereby consolidating previous contradictory reports of Jewish ancestry. We further describe a major difference among Caucasus populations explained by the early presence of Judeans in the Southern and Central Caucasus.
In the same issue, Danielle Venton summarized the conclusion of “the first scientific paper to prove the Khazarian Hypothesis and reject the Rhineland Hypothesis.”
When Behar et al. published “The genome-wide structure of the Jewish people” in 2010, Elhaik decided to investigate the question that had intrigued him for so long. Using data published by Behar, he calculated seven measures of ancestry, relatedness, and geographical origin. Though he used some of the same statistical tests as prior studies, he chose different comparisons.
“Results in the current literature are tangled,” Elhaik says. “Everyone is basically following the same assumption: Ashkenazi Jews are a population isolate, so they are all similar to one another, and this is completely incorrect.”
Previous studies had, for example, combined the question of similarity among and between Jewish populations and the question of ancestry and relatedness to non-Jewish populations. Elhaik viewed these questions separately. Jewish communities are less homogeneous than is popularly thought, he says, with Jewish communities along the former Khazarian border showing the most heterogeneity.
His second question centered on ancestry: When comparing Jewish communities to their non-Jewish neighbors, Caucasus or Levant (Middle Eastern) populations—which is the closest to Jews? “All Eurasian Jewish communities are closer to Caucasus populations,” he writes, with Central European Jews closer to Italian non-Jews as the exception. Not one of the eight evaluated Jewish populations were closer to Levant populations.
29 Feb 2012
Science Daily reports that the count of blood group proteins has been increased for the first time in more than a decade by two more, raising the count from 30 to 32.
You probably know your blood type: A, B, AB or O. You may even know if you’re Rhesus positive or negative. But how about the Langereis blood type? Or the Junior blood type? Positive or negative? Most people have never even heard of these.
Yet this knowledge could be “a matter of life and death,” says University of Vermont biologist Bryan Ballif.
While blood transfusion problems due to Langereis and Junior blood types are rare worldwide, several ethnic populations are at risk, Ballif notes. “More than 50,000 Japanese are thought to be Junior negative and may encounter blood transfusion problems or mother-fetus incompatibility,” he writes.
But the molecular basis of these two blood types has remained a mystery—until now.
In the February issue of Nature Genetics, Ballif and his colleagues report on their discovery of two proteins on red blood cells responsible for these lesser-known blood types.
Ballif identified the two molecules as specialized transport proteins named ABCB6 and ABCG2.
“Only 30 proteins have previously been identified as responsible for a basic blood type,” Ballif notes, “but the count now reaches 32.”
The last new blood group proteins to be discovered were nearly a decade ago, Ballif says, “so it’s pretty remarkable to have two identified this year.”
16 Nov 2009
Are you a genetically a dandelion or an orchid? Both have their place in the evolutionary scheme of things according to a recent article in the Atlantic by David Dobbs.
Most of us have genes that make us as hardy as dandelions: able to take root and survive almost anywhere. A few of us, however, are more like the orchid: fragile and fickle, but capable of blooming spectacularly if given greenhouse care. So holds a provocative new theory of genetics, which asserts that the very genes that give us the most trouble as a species, causing behaviors that are self-destructive and antisocial, also underlie humankind’s phenomenal adaptability and evolutionary success. With a bad environment and poor parenting, orchid children can end up depressed, drug-addicted, or in jail—but with the right environment and good parenting, they can grow up to be society’s most creative, successful, and happy people.
Hat tip to Bird Dog.
17 Jul 2008
British newspapers report that living residents of Nienstedt, a village in the foothills of the Harz Mountains in Lower Saxony, have been found by DNA analysis to be relatives of 3000-year-old Bronze Age inhabitants of the same area interred in the nearby Lichtensteinhöhle cave.
The good news for two villagers in the Söse valley of Germany yesterday was that they have discovered their (127th times)-great grandparents.
The bad news is that their long-lost ancestors may have grilled and eaten other members of their clan.
Every family has its skeletons in the cave, though, so Manfred Hucht-hausen, 58, a teacher, and 48-year-old surveyor Uwe Lange remained in celebratory mood. Thanks to DNA testing of remarkably well-preserved Bronze Age bones, they can claim to have the longest proven family tree in the world. “I can trace my family back by name to 1550,” Mr Lange said. “Now I can go back 120 generations.”
Mr Lange comes from the village of Nienstedt, in Lower Saxony, in the foothills of the Harz mountain range. “We used to play in these caves as kids. If I’d known that there were 3,000-year-old relatives buried there I wouldn’t have set foot in the place.”
The cave, the Lichtensteinhöhle, is made up of five interlocked natural chambers. It stayed hidden from view until 1980 and was not researched properly until 1993. The archaeologist Stefan Flindt found 40 skeletons along with what appeared to be cult objects. ...
Analysis showed that all the bones were from the same family and the scientists speculated that it was a living area and a ceremonial burial place.
About 300 locals agreed to giving saliva swabs. Two of the cave family had a very rare genetic pattern – and a match was found.
The bones of 40 people were shielded from the elements by calcium deposits that formed a protective skin around the skeletons.
All the remains turned out to be from the same family group who had a distinctive – and rare – DNA pattern.
When people in the local area were tested with saliva swabs, two nearby residents turned out to have the same distinctive genetic characteristic.
Manfred Huchthausen, a 58-year-old teacher, and Uwe Lange, a 48-year-old surveyer, now believe they are even more local than either of them thought.
Inma Pazos at iGENEA Forum provides more specific information.
(translated & abridged)
DNA analysis really found that 15 of 22 skeletons were relatives, constituting several generations of a family clan. In 2007, about 300 DNA samples of today’s indigenous population in Osterode-am-Harz were collected and tested for possible affinity. Susann Hummel, a leading anthropologist, has identified eleven living persons as descendants of the cave burials.
Ten lines of mtDNA haplogroup H, four of haplogroup U, two of the haplogroup J and three of the haplogroup T were identified. A further breakdown in the sub-groups succeeded in identifying U5b, T2 and J1b1. In another case, membership in sub-group U2 was considered very likely.
17 Sep 2007
That old goat chasing the young girl is doing mankind a favor, researchers from Stanford and the University of California at Santa Barbara tell us.