A new study, using genetic analysis to look for clues about human migration, suggests that the first modern humans settled in Arabia on their way from the Horn of Africa to the rest of the world about 60,000 years ago.
Led by the University of Leeds and the University of Porto in Portugal, the study is published January 26th in the American Journal of Human Genetics and provides intriguing insight into the earliest stages of modern human migration out of Africa, say the researchers.
Citation: The Arabian cradle: Mitochondrial relicts of the first steps along the southern route out of Africa The American Journal of Human Genetics , 26 January 2012
Authors: Verónica Fernandes1, 2, Farida Alshamali3, Marco Alves1, Marta D. Costa1, 2, Joana B. Pereira1, 2,Nuno M. Silva1, Lotfi Cherni4, 5, Nourdin Harich6, Viktor Cerny7, 8, Pedro Soares1,
Martin B. Richards2, 9,11, Luísa Pereira1, 10, 11.
1 Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Porto 4200-465, Portugal
2 Faculty of Biological Sciences, Institute of Integrative and Comparative Biology, University of Leeds, Leeds LS2 9JT, UK
3 General Department of Forensic Sciences and Criminology, Dubai Police General Headquarters, Dubai 1493, United Arab Emirates
4 Laboratory of Genetics Immunology and Human Pathology, Faculty of Sciences of Tunis, Tunis 2092, Tunisia
5 Higher Institute of Biotechnology of Monastir, Monastir 5000, Tunisia
6 Laboratoire d'Anthropogénétique, Départment de Biologie, Université Chouaïb Doukkali, El Jadida 24000, Morocco
7 Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague 128 43, Czech Republic
8 Institute for Advanced Study, Paris 75648, France
9 School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH, UK
10 Faculdade de Medicina da Universidade do Porto, Porto 4200-319, Portugal
Led by the University of Leeds and the University of Porto in Portugal, the study is published January 26th in the American Journal of Human Genetics and provides intriguing insight into the earliest stages of modern human migration out of Africa, say the researchers.
Credit: University of Leeds
"A major unanswered question regarding the dispersal of modern humans around the world concerns the geographical site of the first steps out of Africa," explains Dr Luísa Pereira from the Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP). "One popular model predicts that the early stages of the dispersal took place across the Red Sea to southern Arabia, but direct genetic evidence has been thin on the ground.":
The international research team, which included colleagues from across Europe, Arabia and North Africa, analysed three of the earliest non-African maternal lineages. These early branches are associated with the time period when modern humans first successfully moved out of Africa.
Using mitochondrial DNA analysis, which traces the female line of descent and is useful for comparing relatedness between different populations, the researchers compared complete genomes from Arabia and the Near East with a database of hundreds more samples from Europe. They found evidence for an ancient ancestry within Arabia.
The researchers, according to Cell Press, "sequenced complete mtDNA genomes from 85 Southwest Asian samples carrying these haplogroups and compared them with a database of 300 European examples. The results show that these minor haplogroups have a relict distribution that suggests an ancient ancestry within the Arabian Peninsula, and they most likely spread from the Gulf Oasis region toward the Near East and Europe during the pluvial period 55–24 ka ago. This pattern suggests that Arabia was indeed the first staging post in the spread of modern humans around the world."
Professor Martin Richards of the University of Leeds' Faculty of Biological Sciences, said: "The timing and pattern of the migration of early modern humans has been a source of much debate and research. Our new results suggest that Arabia, rather than North Africa or the Near East, was the first staging-post in the spread of modern humans around the world."
The research was funded by the Portuguese Foundation for Science and Technology, the Leverhulme Trust, and the DeLaszlo Foundation.
"A major unanswered question regarding the dispersal of modern humans around the world concerns the geographical site of the first steps out of Africa," explains Dr Luísa Pereira from the Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP). "One popular model predicts that the early stages of the dispersal took place across the Red Sea to southern Arabia, but direct genetic evidence has been thin on the ground.":
The international research team, which included colleagues from across Europe, Arabia and North Africa, analysed three of the earliest non-African maternal lineages. These early branches are associated with the time period when modern humans first successfully moved out of Africa.
Using mitochondrial DNA analysis, which traces the female line of descent and is useful for comparing relatedness between different populations, the researchers compared complete genomes from Arabia and the Near East with a database of hundreds more samples from Europe. They found evidence for an ancient ancestry within Arabia.
In human genetics, the haplogroups most commonly studied are Y-chromosome (Y-DNA) haplogroups and mitochondrial DNA (mtDNA) haplogroups, both of which can be used to define genetic populations. Y-DNA is passed solely along the patrilineal line, from father to son, while mtDNA is passed down the matrilineal line, from mother to offspring of both sexes. Neither recombines, and thus Y-DNA and mtDNA change only by chance mutation at each generation with no intermixture between parents' genetic material.
The researchers, according to Cell Press, "sequenced complete mtDNA genomes from 85 Southwest Asian samples carrying these haplogroups and compared them with a database of 300 European examples. The results show that these minor haplogroups have a relict distribution that suggests an ancient ancestry within the Arabian Peninsula, and they most likely spread from the Gulf Oasis region toward the Near East and Europe during the pluvial period 55–24 ka ago. This pattern suggests that Arabia was indeed the first staging post in the spread of modern humans around the world."
Professor Martin Richards of the University of Leeds' Faculty of Biological Sciences, said: "The timing and pattern of the migration of early modern humans has been a source of much debate and research. Our new results suggest that Arabia, rather than North Africa or the Near East, was the first staging-post in the spread of modern humans around the world."
The research was funded by the Portuguese Foundation for Science and Technology, the Leverhulme Trust, and the DeLaszlo Foundation.
Anatomical comparison of the skulls of a modern human (left) and Homo neanderthalensis (right).
Credit: Wikipedia
Professor Martin Richards is the UK's only Professor of Archaeogenetics. He is now based at the University of Huddersfield and retains a Visiting Chair at the University of Leeds. Archaeogenetics is the use of genetic data to address questions concerning archaeology and human evolution. His research has focused on studies of mitochondrial DNA and the Y chromosome, and how results of these studies can inform our knowledge of prehistoric patterns of migration.
Contacts and sources:
University of Leeds
Professor Martin Richards, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH
Dr Luísa Pereira, IPATIMUPa (Instituto de Patologia e Imunologia Molecular da Universidade do Porto)
Jo Kelly, Campus PR
University of Leeds
Professor Martin Richards, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH
Dr Luísa Pereira, IPATIMUPa (Instituto de Patologia e Imunologia Molecular da Universidade do Porto)
Jo Kelly, Campus PR
Citation: The Arabian cradle: Mitochondrial relicts of the first steps along the southern route out of Africa The American Journal of Human Genetics , 26 January 2012
Authors: Verónica Fernandes1, 2, Farida Alshamali3, Marco Alves1, Marta D. Costa1, 2, Joana B. Pereira1, 2,Nuno M. Silva1, Lotfi Cherni4, 5, Nourdin Harich6, Viktor Cerny7, 8, Pedro Soares1,
Martin B. Richards2, 9,11, Luísa Pereira1, 10, 11.
1 Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Porto 4200-465, Portugal
2 Faculty of Biological Sciences, Institute of Integrative and Comparative Biology, University of Leeds, Leeds LS2 9JT, UK
3 General Department of Forensic Sciences and Criminology, Dubai Police General Headquarters, Dubai 1493, United Arab Emirates
4 Laboratory of Genetics Immunology and Human Pathology, Faculty of Sciences of Tunis, Tunis 2092, Tunisia
5 Higher Institute of Biotechnology of Monastir, Monastir 5000, Tunisia
6 Laboratoire d'Anthropogénétique, Départment de Biologie, Université Chouaïb Doukkali, El Jadida 24000, Morocco
7 Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague 128 43, Czech Republic
8 Institute for Advanced Study, Paris 75648, France
9 School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH, UK
10 Faculdade de Medicina da Universidade do Porto, Porto 4200-319, Portugal
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