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Susumu Ohno
was a Japanese-American geneticist and evolutionary biologist, and seminal researcher in the field of molecular evolution. Biography Susumu Ohno was born to Japanese parents in Keijō, Chōsen (present-day Seoul, South Korea), Empire of Japan on February 1, 1928. The second of five children, he was the son of the minister of education of the Japanese Protectorate of Korea. The family returned to mainland Japan after the war in 1945. He later became a citizen of the United States. Susumu Ohno married musician Midori Aoyama in 1951. They had two sons and one daughter. His passion for science derived from his lifelong love of horses. He earned a Ph.D. in veterinary science at Tokyo University of Agriculture and Technology in 1949, and later a Ph.D. and D.Sc. from Hokkaido University. He went to the United States in 1951, as a visiting scholar to UCLA, and in 1952 joined the new research department at City of Hope Medical Center, where he remained in active research until 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keijō
, or Gyeongseong (), was an administrative district of Korea under Japanese rule that corresponds to the present Seoul, the capital of South Korea. History When the Empire of Japan annexed the Korean Empire, it made Seoul the colonial capital. While under colonial rule (1910–1945), the city was called Keijō (; , literally meaning "capital city" in Hanja Hanja (; ), alternatively spelled Hancha, are Chinese characters used to write the Korean language. After characters were introduced to Korea to write Literary Chinese, they were adapted to write Korean as early as the Gojoseon period. () ....). Keijō was an urban city () that had 2 wards: Keijō itself and Ryusan-ku (龍山區, , ). Gyeongseong was part of Gyeonggi Province, instead of being an independent city or prefecture as in Joseon and present days. In 1914, several outer districts of the prefecture were annexed to neighboring Goyang County (now Goyang City, reducing the administrative size of the prefe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barr Body
A Barr body (named after discoverer Murray Barr) or X-chromatin is an inactive X chromosome. In species with XY sex-determination (including humans), females typically have two X chromosomes, and one is rendered inactive in a process called lyonization. Errors in chromosome separation can also result in male and female individuals with extra X chromosomes. The Lyon hypothesis states that in cells with multiple X chromosomes, all but one are inactivated early in embryonic development in mammals.Brown, C.J., Robinson, W.P., (1997), XIST Expression and X-Chromosome Inactivation in Human Preimplantation Embryos ''Am. J. Hum. Genet.'' 61, 5–8Full Text PDF The X chromosomes that become inactivated are chosen randomly, except in marsupials and in some extra-embryonic tissues of some placental mammals, in which the X chromosome from the sperm is always deactivated. In humans with euploidy, a genotypical female (46, XX karyotype) has one Barr body per somatic cell nucleus, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japanese Geneticists
Japanese may refer to: * Something from or related to Japan, an island country in East Asia * Japanese language, spoken mainly in Japan * Japanese people, the ethnic group that identifies with Japan through ancestry or culture ** Japanese diaspora, Japanese emigrants and their descendants around the world * Japanese citizens, nationals of Japan under Japanese nationality law ** Foreign-born Japanese, naturalized citizens of Japan * Japanese writing system, consisting of kanji and kana * Japanese cuisine, the food and food culture of Japan See also * List of Japanese people * * Japonica (other) * Japanese studies , sometimes known as Japanology in Europe, is a sub-field of area studies or East Asian studies involved in social sciences and humanities research on Japan. It incorporates fields such as the study of Japanese language, history, culture, litera ... {{disambiguation Language and nationality disambiguation pages ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary Biologists
Evolutionary biology is the subfield of biology that studies the evolutionary processes such as natural selection, common descent, and speciation that produced the diversity of life on Earth. In the 1930s, the discipline of evolutionary biology emerged through what Julian Huxley called the modern synthesis of understanding, from previously unrelated fields of biological research, such as genetics and ecology, systematics, and paleontology. The investigational range of current research has widened to encompass the genetic architecture of adaptation, molecular evolution, and the different forces that contribute to evolution, such as sexual selection, genetic drift, and biogeography. The newer field of evolutionary developmental biology ("evo-devo") investigates how embryogenesis is controlled, thus yielding a wider synthesis that integrates developmental biology with the fields of study covered by the earlier evolutionary synthesis. Subfields Evolution is the central ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Scientists Of Asian Descent
American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, people who self-identify their ancestry as "American" ** American English, the set of varieties of the English language native to the United States ** Native Americans in the United States, indigenous peoples of the United States * American, something of, from, or related to the Americas, also known as "America" ** Indigenous peoples of the Americas * American (word), for analysis and history of the meanings in various contexts Organizations * American Airlines, U.S.-based airline headquartered in Fort Worth, Texas * American Athletic Conference, an American college athletic conference * American Recordings (record label), a record label that was previously known as Def American * American University, in Washington, D.C. Sports teams S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2000 Deaths
This is a list of lists of deaths of notable people, organized by year. New deaths articles are added to their respective month (e.g., Deaths in ) and then linked below. 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 1993 1992 1991 1990 1989 1988 1987 1986 Earlier years ''Deaths in years earlier than this can usually be found in the main articles of the years.'' See also * Lists of deaths by day * Deaths by year (category) {{DEFAULTSORT:deaths by year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1928 Births
Events January * January – British bacteriologist Frederick Griffith reports the results of Griffith's experiment, indirectly demonstrating that DNA is the genetic material. * January 1 – Eastern Bloc emigration and defection: Boris Bazhanov, Joseph Stalin's personal secretary, crosses the border to Iran to defect from the Soviet Union. * January 17 – The OGPU arrests Leon Trotsky in Moscow; he assumes a status of passive resistance and is exiled with his family. * January 26 – The volcanic island Anak Krakatau appears. February * February – The Ford River Rouge Complex at Dearborn, Michigan, an automobile plant begun in 1917, is completed as the world's largest integrated factory. * February 8 – Scottish-born inventor John Logie Baird broadcasts a transatlantic television signal from London to Hartsdale, New York. * February 11 – February 19, 19 – The 1928 Winter Olympics are held in St. Moritz, Switzerland, the first as a separate event. Sonja Henie of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleopolyploidy
Paleopolyploidy is the result of genome duplications which occurred at least several million years ago (MYA). Such an event could either double the genome of a single species (autopolyploidy) or combine those of two species (allopolyploidy). Because of functional Gene redundancy, redundancy, genes are rapidly silenced or lost from the duplicated genomes. Most paleopolyploids, through evolutionary time, have lost their polyploid status through a process called diploidization, and are currently considered diploids, e.g., baker's yeast, ''Arabidopsis thaliana'', and perhaps humans. Paleopolyploidy is extensively studied in plant lineages. It has been found that almost all flowering plants have undergone at least one round of genome duplication at some point during their evolutionary history. Ancient genome duplications are also found in the early ancestor of vertebrates (which includes the human lineage) near the origin of the bony fishes, and another in the stem lineage of teleo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Duplication
Gene duplication (or chromosomal duplication or gene amplification) is a major mechanism through which new genetic material is generated during molecular evolution. It can be defined as any duplication of a region of DNA that contains a gene. Gene duplications can arise as products of several types of errors in DNA replication and repair machinery as well as through fortuitous capture by selfish genetic elements. Common sources of gene duplications include ectopic recombination, retrotransposition event, aneuploidy, polyploidy, and replication slippage. Mechanisms of duplication Ectopic recombination Duplications arise from an event termed unequal crossing-over that occurs during meiosis between misaligned homologous chromosomes. The chance of it happening is a function of the degree of sharing of repetitive elements between two chromosomes. The products of this recombination are a duplication at the site of the exchange and a reciprocal deletion. Ectopic recombina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Junk DNA
Junk DNA (non-functional DNA) is a DNA sequence that has no known biological function. Most organisms have some junk DNA in their genomes—mostly pseudogenes and fragments of transposons and viruses—but it is possible that some organisms have substantial amounts of junk DNA. All protein-coding regions are generally considered to be functional elements in genomes. Additionally, non-protein coding regions such as genes for ribosomal RNA and transfer RNA, regulatory sequences, origins of replication, centromeres, telomeres, and scaffold attachment regions are considered as functional elements. (See Non-coding DNA for more information.) It is difficult to determine whether other regions of the genome are functional or nonfunctional. There is considerable controversy over which criteria should be used to identify function. Many scientists have an evolutionary view of the genome and they prefer criteria based on whether DNA sequences are preserved by natural selection. Oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ohno's Law
Ohno's law was proposed by a Japanese-American biologist Susumu Ohno, saying that the gene content of the mammalian species has been conserved over species not only in the DNA content but also in the genes themselves. That is, nearly all mammalian species have conserved the X chromosome from their primordial X chromosome of a common ancestor.Ohno S (1967). ''Sex Chromosomes and sex-linked genes.'' Berlin:Springer-Verlag. Evidence Mammalian X chromosomes in various species, including human and mouse, have nearly the same size, with the content of about 5% of the genome. Additionally, for individual gene loci, a number of X-linked genes are common through mammalian species. Examples include glucose-6-phosphate dehydrogenase (G6PD), and the genes for Factor VIII and Factor IX. Moreover, no instances were found where an X-linked gene in one species was located on an autosome in the other species. Conservation mechanisms The content of a chromosome would be changed mainly by mut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
