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Sunday, October 2, 2022

Our Jewish Genes As the Geneticists See them

 Nadene Goldfoot                                               


Recent studies have been conducted on a large number of genes, homologous chromosomes or autosomes (all chromosomes except chromosomes X and Y). We have 23 chromosomes and the X and Y, the 23rd, are the sex genes with X being female and Y being the male line.   Actually, we have 46; 23 from each parent.  

These 46 chromosomes carry the genetic information that’s passed from parent to child through heredity. It is the very detail of this genetic material – in the DNA – that makes most people (other than identical siblings) totally unique.

The total number of chromosomes in an organism, such as an animal or plant, is important and differs for different species. Some insects, for instance, only have one or two chromosomes. Meanwhile, giraffes have 62, chickens have 78, mice have 40, cabbages 18, and strawberries only 14. Humans, like many other species, are called ‘diploid’. This is because our chromosomes exist in matching pairs – with one chromosome of each pair being inherited from each biological parent.

Every cell in the human body contains 23 pairs of such chromosomes; our diploid number is therefore 46, our ‘haploid’ number 23. Of the 23 pairs, 22 are known as autosomes. The 23rd pair is made up of the sex chromosomes, called the ‘X’ and ‘Y’ chromosome. This is the pair of chromosomes that is responsible for ‘sex-linked’ medical conditions that pass through some families, such as the blood disorder haemophilia, which affects mainly males. Females have a pair of X chromosomes, males have an X and Y chromosome. 

A 2009 study was able to genetically identify individuals with full or partial Ashkenazi Jewish ancestry.  

Harry Ostrer is a medical geneticist who investigates the genetic basis of common and rare disorders. In the diagnostic laboratory, he translates the findings of genetic discoveries into tests that can be used to identify people's risks for disease prior to occurrence, or for predicting its outcome once it has occurred. He is also known for his study, writing and lectures on the origins of the Jewish people.

He is a Professor of Pathology and Genetics at Albert Einstein College of Medicine of Yeshiva University and Director of Genetic and Genomic Testing at Montefiore Medical Center.

For the prior 21 years he was Professor of Pediatrics, Pathology and Medicine and Director of the Human Genetics Program at New York University School of Medicine.


 In August 2012, Dr. Harry Ostrer in his book Legacy: A Genetic History of the Jewish People, summarized his and other work in genetics of the last 20 years, and concluded that all major Jewish groups share a common Middle Eastern origin. Ostrer also refuted the Khazar hypothesis of Ashkenazi ancestry. 

Citing autosomal DNA studies, Nicholas Wade estimates that "Ashkenazic and Sephardic Jews have roughly 30 percent European ancestry, with most of the rest from the Middle East." He further noticed that "The two communities seem very similar to each other genetically, which is unexpected because they have been separated for so long." Concerning this relationship he points to Atzmon's conclusions that "the shared genetic elements suggest that members of any Jewish community are related to one another as closely as are fourth or fifth cousins in a large population, which is about 10 times higher than the relationship between two people chosen at random off the streets of New York City".

 Concerning North African Jews, autosomal genetic analysis in 2012 revealed that North African Jews are genetically close to European Jews. This finding "shows that North African Jews date to biblical-era Israel, and are not largely the descendants of natives who converted to Judaism,

" Y DNA studies examine various paternal lineages of modern Jewish populations. Such studies tend to imply a small number of founders in an old population whose members parted and followed different migration paths.

 In most Jewish populations, these male line ancestors appear to have been mainly Middle Eastern. For example, Ashkenazi Jews share more common paternal lineages with other Jewish and Middle Eastern groups than with non-Jewish populations in areas where Jews lived in Eastern Europe, Germany and the Rhine Valley. This is consistent with Jewish traditions in placing most Jewish paternal origins in the region of the Middle East.                  

Doron M. Behar, Founder and CEO of Igentify | Genetics and genomics enthusiast | Committed to advancing the digital genomic revolution, Haifa, Israel, said, "I am a population geneticist and physician dedicated to changing the way that genetic information is uncovered and used. I’m working to bring digital health, genomics, and technology together, alongside my colleagues at Igentify. We help clinicians, laboratories, and patients access, interpret, and use genetic information and education more effectively. I’m proud to lead Igentify in its work generating optimism for change and synergizing the genomic and digital revolutions. I enjoy collaborating with others who share our vision for actionable and accessible genomic data for all.

A study conducted in 2013 by Doron  M. Behar, 

MD, PhD et al. found no evidence of a Khazar origin for Ashkenazi Jews and suggested that "Ashkenazi Jews share the greatest genetic ancestry with other Jewish populations, and among non-Jewish populations, with groups from Europe and the Middle East. No particular similarity of Ashkenazi Jews with populations from the Caucasus is evident, particularly with the populations that most closely represent the Khazar region. In this view, analysis of Ashkenazi Jews, together with a large sample from the region of the Khazar Khaganate, corroborates earlier results that Ashkenazi Jews derive their ancestry primarily from populations of the Middle East and Europe, that they possess considerable shared ancestry with other Jewish populations, and that there is no indication of a significant genetic contribution either from within or from north of the Caucasus region."
 THE CANAANITES

A 2020 study on remains from Bronze Age southern Levantine (Canaanite) populations found evidence of large scale migration from the Zagros or Caucasus into the southern Levant by the Bronze Age and increasing over time (resulting in a Canaanite population descended from both those migrants and earlier Neolithic Levantine peoples). 

The results were found to be consistent with several Jewish groups (including Mizrahi, Ashkenazi, and Sephardic Moroccan Jews) and non-Jewish Arabic-speaking Levantine populations (such as Lebanese, Druze, Palestinians, and Syrians) deriving about half or more of their ancestry from populations related to those from the Bronze Age Levant and Chalcolithic Zagros. The study modeled the aforementioned groups as having ancestry from both ancient populations. (So it's the non-Jewish genes they share.)

Approximately 35% to 43% of Jewish men are in the paternal line known as haplogroup J and its sub-haplogroups. This haplogroup is particularly present in the Middle East and Southern Europe. 15% to 30% are in haplogroup E1b1b, (or E-M35) and its sub-haplogroups which is common in the Middle EastNorth Africa, and Southern Europe.                                   

                                        Israeli Jews

Israeli Jews belong by and large to the Ashkenazi (German, Central and Eastern European) division of world Jews, although there are minority representations from the Sephardic (Spanish) and Mizrahi (Middle Eastern) divisions. They number over 6 million inhabitants and comprise 75% of the population of the Middle Eastern state of Israel, founded in 1949. The overwhelming majority are non-Haredi or not strictly Orthodox by religion. Ethnically and genetically, they derive from European populations that were largely eliminated during the Holocaust and are thus no longer present in significant numbers in present-day European nations. European Jewry after World War II was transplanted and has been divided almost equally between Israel and the United States. See Demographics of Israel.

The Israeli Jews population data represent DNA samples from 163 unrelated mixed Jewish Caucasians of both sexes obtained by the Department of Human Genetics, Tel-Aviv University, Israel in 2004. A European Standard Set (ESS) of DNA loci was used, compiling allele distributions for 10 short tandem repeat (STR) polymorphic markers as used in forensic and paternity testing with the commercial AmpFISTR SGM Plus kit developed by Applied Biosystems.

Treasures of Jewish Art: From the Jacobo and Asea Furman Collection of Judaica, possibly Sepharic 

In 1992 G. Lucotte and F. David were the first genetic researchers to have documented a common paternal genetic heritage between Sephardi and Ashkenazi Jews. Another study published just a year later suggested the Middle Eastern origin of Jewish paternal lineages.

Michael Hammer, PhD, is a professor and research scientist.  Dr. Hammer is a Research Scientist in the ARL Division of Biotechnology at the University of Arizona with joint appointments in Neurology and Ecology and Evolutionary Biology, and is a member of the Steele Children’s Research Center, Bio5, and the Arizona Cancer Center. Dr. Hammer’s research spans the fields of medical genetics and human population genetics. For the past 20 years, Dr. Hammer’s group has published over 100 articles documenting the African origin of human diversity, interbreeding between modern humans and archaic forms of the genus Homo, and genome diversity in the great apes. In the last 3 years, his research team has successfully employed next generation sequencing technologies to identify genetic variants causing neurodevelopmental disorders in undiagnosed children. This has led to the publication of articles identifying pathogenic variants associated with early onset epileptic encephalopathies. His lab is also pursuing studies to identify modifier genes that alter the expression of major genes and how they contribute to the molecular basis of clinical variability in Mendelian disorders.

In 2000, Michael Hammer, PhD,, et al. conducted a study on 1,371 men and definitively established that part of the paternal gene pool of Jewish communities in Europe, North Africa and Middle East came from a common Middle East ancestral population. They suggested that most Jewish communities in the Diaspora remained relatively isolated and endogamous compared to non-Jewish neighbor populations.

Investigations made by Nebel et al. on the genetic relationships among Ashkenazi Jews, Kurdish and Sephardi (North Africa, Turkey, Iberian Peninsula, Iraq and Syria) indicate that Jews are more genetically similar to groups in the northern Fertile Crescent (Kurds, Turks and Armenians) than their Arab neighbors, and suggest that some of this difference might be due to migration and admixture from the Arabian peninsula during the last two millennia (into certain current Arabic-speaking populations). Considering the timing of this origin, the study found that "the common genetic Middle Eastern background (of Jewish populations) predates the ethnogenesis in the region and concludes that the Y chromosome pool of Jews is an integral part of the genetic landscape of Middle East.

                       Priestly families:Cohanim

Nephrologist Dr. Karl Skorecki decided to analyze the Cohanim to see if they were the descendants of one man, in which case they should have a set of common genetic markers.

To test this hypothesis, he contacted Dr. Michael Hammer of the University of Arizona, a researcher in molecular genetics and a pioneer in research on chromosomes. Their article, published in Nature in 1997, has had some impact. A set of special markers (called Cohen Modal Haplotype or CMH) was defined as one which is more likely to be present in the Cohanim, defined as contemporary Jews named Cohen or a derivative, and it was proposed that this results from a common descent from the ancient priestly lineage than from the Jewish population in general.

But, subsequent studies showed that the number of genetic markers used and the number of samples (of people saying Cohen) were not big enough. The last study, conducted in 2009 by Hammer and Behar et al., says 20 of the 21 Cohen haplogroups have no single common young haplogroup; five haplogroups comprise 79.5% of all haplogroups of Cohen. Among these first 5 haplogroups, J-P58 (or J1E) accounts for 46.1% of Cohen and the second major haplogroup, J-M410 or J2a accounts for 14.4%.

 Hammer and Behar have redefined an extended CMH haplotype as determined by a set of 12 markers and having as "background" haplogroup determining the most important lines J1E (46.1%). This haplotype is absent among non-Jews in 2009 analyzed in the study. This divergence would appear to be from 3000 ± 1000 years ago. This study nevertheless confirms that the current Cohen lineage descended from a small number of paternal ancestors.

In the summary of their findings the authors concluded that " Our estimates of the coalescence time also lend support to the hypothesis that the extended CMH represents a unique founding lineage of the ancient Hebrews that has been paternally inherited along with the Jewish priesthood."

Molecular phylogenetics research published in 2013 and 2016 for Levant haplogroup J1 (J-M267) places the Y-chromosomal Aaron within subhaplogroup Z18271, age estimate 2638–3280 years Before Present (yBP). Moses was born in 1391 BCE, so Aaron, his brother, was born in 1395 BCE, which was 3,417 years ago., fitting in with 3,280 time frame of the scientists.

A leader of the Lemba people, wearing a prayer shawl, gathers with his fellow Jews. DNA tests have confirmed the Semitic heritage of these sub-Saharan Africans.

Jekesai Njikizana /AFP/Getty Images

The Lemba of South Africa, a Bantu speaking people whose culture forbids pork and requires male circumcision, have high frequencies of the Middle Eastern Y-chromosome HgJ-12f2a (25%), a potentially SEA Y, Hg-K(xPQR) (32%) and a Bantu Y, E-PN1 (30%) (similar to E-M2). The Lemba tribe of Venda in South Africa claims to be Jewish and to have originated in Sena – possibly Yemenite Sena in Wadi Masila of the Hadramaut. There are indications of genetic connections with the Hadramaut, i.e., the Lemba Y-chromosomes and Hadramaut Y-chromosomes showed overlap. In addition, there was also present a Cohen Modal Haplotype (CMH) within their subclan, the Buba – higher than the general Jewish population. It has been suggested by Tudor Parfitt and Yulia Egorova that their Jewish ancestors probably came along with general Semitic incursions into East Africa from South Arabia, and then moved slowly south through the area of Great Zimbabwe.

Resource:

https://en.wikipedia.org/wiki/Genetic_studies_on_Jews#:~:text=in%20one%20sample.-,Y%2DDNA%20of%20Ethiopian%20Jews,Ethiopia%2C%20not%20the%20Middle%20East.

https://dnaconsultants.com/israeli-jews/

https://neurology.arizona.edu/michael-hammer-phd

https://il.linkedin.com/in/doron-m-behar-md-phd-b8b0ba137

https://www.jewishvirtuallibrary.org/zimbabwe-s-quot-black-jews-quot-the-lemba-people

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