5月6日,，在南非約翰內(nèi)斯堡,，一名參觀者注視著200多萬年前的猿人完整頭蓋骨“普萊斯夫人”。自從1947年在南非斯泰克方丹出土以來,，這枚轟動世界的頭蓋骨今年5月第一次公開展出,。斯泰克方丹位于南非最大城市約翰內(nèi)斯堡西北約50公里，其山谷洞穴內(nèi)的化石記載著過去350萬年里人類進(jìn)化的信息,。新華社發(fā)（南非新聞聯(lián)合社）

美國等國一些科學(xué)家最新研究顯示,，非洲人基因最多元。這項研究結(jié)果還進(jìn)一步佐證人類起源非洲說,，將人類進(jìn)化起源地范圍縮小至今天南非和納米比亞邊境附近,。

美國《科學(xué)》周刊電子版4月30日刊登這份研究報告。研究人員通過10多年非洲實(shí)地工作,、比對分析不同族群基因信息后發(fā)現(xiàn),，非洲人基因變異最劇。

“基于現(xiàn)代人類起源非洲說,，他們（非洲人）有時間展開強(qiáng)烈基因變異,，”研究團(tuán)隊負(fù)責(zé)人、美國賓夕法尼亞大學(xué)女遺傳學(xué)家莎拉·蒂什科夫說,。

她進(jìn)一步解釋,，這意味著非洲人在不斷適應(yīng)非洲大陸多變自然環(huán)境的過程中，基因同時發(fā)生變異,。

研究人員說,，科學(xué)家先前對非洲人的基因變異知之甚少。這項研究發(fā)現(xiàn)對于找到疾病對不同族群影響存在差異的原因,、進(jìn)而為對抗這些疾病“設(shè)計”不同治療方案至關(guān)重要,。（生物谷Bioon.com）

生物谷推薦原始出處：

Science DOI: 10.1126/science.1172257

The Genetic Structure and History of Africans and African Americans

Sarah A. Tishkoff 1*, Floyd A. Reed 2, Fran?oise R. Friedlaender 3, Christopher Ehret 4, Alessia Ranciaro 5, Alain Froment 6, Jibril B. Hirbo 1, Agnes A. Awomoyi 7, Jean-Marie Bodo 8, Ogobara Doumbo 9, Muntaser Ibrahim 10, Abdalla T. Juma 10, Maritha J. Kotze 11, Godfrey Lema 12, Jason H. Moore 13, Holly Mortensen 14, Thomas B. Nyambo 12, Sabah A. Omar 15, Kweli Powell 16, Gideon S. Pretorius 17, Michael W. Smith 18, Mahamadou A. Thera 9, Charles Wambebe 19, James L. Weber 20, Scott M. Williams 21

1 Department of Biology, University of Maryland, College Park, MD 20742, USA.; Departments of Genetics and Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
2 Department of Biology, University of Maryland, College Park, MD 20742, USA.; Present address: Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Biology, 24306 Pl?n, Germany.
3 Independent researcher, Sharon, CT 06069, USA.
4 Department of History, University of California, Los Angeles, CA 90095, USA.
5 Department of Biology, University of Maryland, College Park, MD 20742, USA.; Departments of Genetics and Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.; Dipartimento di Biologia ed Evoluzione, Università di Ferrara, 44100 Ferrara, Italy.
6 UMR 208, IRD-MNHN, Musée de l’Homme, 75116 Paris, France.
7 Department of Biology, University of Maryland, College Park, MD 20742, USA.; Present address: Department of Internal Medicine, Ohio State University, Columbus, OH 43210, USA.
8 Ministère de la Recherche Scientifique et de l’Innovation, BP 1457, Yaoundé, Cameroon.
9 Malaria Research and Training Center, University of Bamako, Bamako, Mali.
10 Department of Molecular Biology, Institute of Endemic Diseases, University of Khartoum, 15-13 Khartoum, Sudan.
11 Department of Pathology, Faculty of Health Sciences, University of Stellenbosch, Tygerberg 7505, South Africa.
12 Department of Biochemistry, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania.
13 Departments of Genetics and Community and Family Medicine, Dartmouth Medical School, Lebanon, NH 03756, USA.
14 Department of Biology, University of Maryland, College Park, MD 20742, USA.; Present address: Office of Research and Development, National Center for Computational Toxicology, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
15 Kenya Medical Research Institute, Center for Biotechnology Research and Development, 54840-00200 Nairobi, Kenya.
16 Department of Biology, University of Maryland, College Park, MD 20742, USA.; Present address: College of Education, University of Maryland, College Park, MD 20742, USA.
17 Division of Human Genetics, Faculty of Health Sciences, University of Stellenbosch, Tygerberg 7505, South Africa.
18 Laboratory of Genomic Diversity, National Cancer Institute, Frederick, MD 21702, USA.
19 International Biomedical Research in Africa, Abuja, Nigeria.
20 Marshfield Clinic Research Foundation, Marshfield, WI 54449, USA.
21 Department of Molecular Physiology and Biophysics, Center for Human Genetics Research, Vanderbilt University, Nashville, TN 37232, USA.
* To whom correspondence should be addressed.

Africa is the source of all modern humans, but characterization of genetic variation and of relationships among populations across the continent has been enigmatic. We studied 121 African populations, 4 African American populations, and 60 non-African populations for patterns of variation at 1327 nuclear microsatellite and insertion/deletion markers. We identified 14 ancestral population clusters in Africa that correlate with self-described ethnicity and shared cultural and/or linguistic properties. We observe high levels of mixed ancestry in most populations, reflecting historic migration events across the continent. Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan-speakers and Pygmies). The ancestry of African Americans is predominantly from Niger-Kordofanian (~71%), European (~13%), and other African (~8%) populations, although admixture levels varied considerably among individuals. This study helps tease apart the complex evolutionary history of Africans and African Americans, aiding both anthropological and genetic epidemiologic studies.