Research into Population Genetics 背景知识(background info)

1. Luca Cavalli-Sforza: Cavalli-Sforza, born in Genoa, Italy, was educated at the University of Pavia where he gained his MD in 1944. After working on bacterial genetics at Cambridge (1948－1950) and Milan (1950－1957) he has held chairs in genetics at Parma (1958－1962) and Pavia (1962－1970). In 1970 he was appointed professor of genetics at the University of Stanford, California, a position he held until his retirement in 1992. Cavalli-Sforza has specialized mainly in the genetics of human populations, producing with Walter Bodmer a comprehensive survey of the subject in their Genetics, Evolution and Man (1976). He has also done much to show how genetic data from present human racial groups could be used to reconstruct their past separations. This reconstruction, based on the analysis of 58 genes, yields a bifurcated evolutionary tree with Caucasian and African races in one branch and Orientals, Oceanians, and Amerinds in the other. For more information, check out the web page at http:www.balzan.it/english/pb1999/cavalli/laudatio_profilo.htm. The web page at http://www.balzan.it/english/pb1999/cavalli/paper.htm is a summary of Dr. Cavalli-Sforza's research in his own words.


2. Columbus: Christopher Columbus, an Italian-born master navigator (born in Genoa, Italy in 1451 and died at Valladolid, Spain in 1506) who sailed in the service of Spain, is commonly described as the discoverer of the New World — America. His four transatlantic voyages (1492－1493, 1493－1496, 1498－1500, and 1502－1504) opened the way for European exploration, exploitation, and colonization of the Americas. Columbus's real greatness lies in the fact that having found the West Indies — making major errors in his navigational computations and location in doing so — he was able to find his way back to Europe and return to the Indies. It is as the result of Columbus's “discovery” that the New World became part of the European world. For more detailed information about Christopher Columbus and his voyages (including timeline, photos, etc.), please visit the websites at http://memory.loc.gov/ammem/today/oct12.html and http://www.kidsdomain.com/holiday/columbusday.html. An account of the historical background about Columbus's exploration can be found at http://muweb.millersville.edu/~columbus/columbus.html. The web page at http://www.hartford-hwp.com/Taino/docs/columbus.html provides a different perspective on the controversy concerning the dark side of Columbus's “discovery” of the Americas.


3. human genetic map: Our bodies are comprised of trillions of microscopic units called cells. Cells in turn are built up from many specific types of molecules, both large and small. The large molecules or macromolecules include polysaccharides, nucleic acids and proteins. Proteins are the workhorses of our cells. There are about 40,000 different types of proteins in our bodies. Each protein is present in many, many copies. An adult, for example, carries about 1021 (a billion trillion) hemoglobin molecules. The flow of genetic information is from DNA to RNA to Protein. Each protein is a linear polymer of a specific sequence of 20 different amino acids. DNA is also a linear polymer comprised of 4 types of nucleotides. The sequence of amino acids in each protein is encoded by a segment of DNA called a gene. Three consecutive nucleotides in a gene encode a single amino acid in the corresponding protein. The genetic code is universal among all living things. For more information about human genetics as well as related research, check out the website at http://research.marshfieldclinic.org/genetics/Educational_Material/GPrinciples.htm.


4. Khoisan: Khoisan is the name by which the lighter skinned indigenous peoples of southern Africa, the Khoi (Hottentots) and the San (Bushmen) are known. These people were the earliest inhabitants of Africa and dominated the sub-continent for millennia before the appearance of the Nguni and other black peoples. There were probably about 120,000 living in South Africa around 1500. For more information about the Khoisan people and culture, check out the websites at http://www.museums.org.za/sam/resource/arch/khoisan.htm and http://www.khoisan.org.


5. Basques: The Basques are a people who live in a small region (about the size of Rhode Island in the United States) that straddles the border of Spain and France from the sea in the west into the Pyrenees in the east. This area is called Euskal Herria (comprising seven provinces, historically: Araba, Bizkaia, Gipuzkoa, and Navarra on the Spanish side; Laburdi, Zuberoa, and Behe-Nafarroa on the French side). There are about 660,000, according to the 1991 census. Fewer than 80,000 of these are on the French side of the frontier which runs through the Basque Country, the rest on the Spanish side. Basques speak a language called euskara, but today only about 25% of the population is fluent in that tongue. Even so, the word for a Basque person, euskaldun, means “possessor of the Basque language”. The Basque population is distinguished physically by a high incidence of Rh Negative factor in the blood. No one knows exactly where the Basques came from. Some say they have lived in that area since Cro-Magnon man first roamed Europe. Estimates of how long they have lived there vary from 10,000 to 75,000 years. Some say they are descended from the original Iberians. More fanciful theories exist, as well. One is that the Basques are the descendents of the survivors of Atlantis. For more information about the Basque people, language and culture, check out the websites at http://www.cogs.susx.ac.uk/users/larryt/basque.faqs.html, http://www.buber.net/Basque/ and http://www.basqueheritage.com.