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Microcephalin
Microcephalin (MCPH1) is a gene that is expressed during fetal brain development. Certain mutations in ''MCPH1'', when homozygous, cause primary microcephaly—a severely diminished brain. Hence, it has been assumed that variants have a role in brain development. However, in normal individuals no effect on mental ability or behavior has yet been demonstrated in either this or another similarly studied microcephaly gene, '' ASPM''. However, an association has been established between normal variation in brain structure, as measured with MRI (i.e., primarily '' cortical surface area'' and total brain volume) but only in females, and common genetic variants within both the MCPH1 gene and another similarly studied microcephaly gene, ''CDK5RAP2''. Structure Microcephalin proteins contain the following three domains: * N-terminal BRCT domain * Central microcephalin protein domain () * C-terminal BRCT domain Expression in the brain MCPH1 is expressed in the fetal brain, in the develo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bruce Lahn
Bruce Lahn is a Chinese-born American geneticist. Lahn came to the U.S. from China to continue his education in the late 1980s. He is the William B. Graham professor of Human Genetics at the University of Chicago. He is also the founder of the Center for Stem Cell Biology and Tissue Engineering at Sun Yat-sen University in Guangzhou, China. Lahn currently serves as the chief scientist of VectorBuilder, Inc. Lahn's honors include the TR100 Award from ''Technology Review'' magazine, the Merrill Lynch Forum Global Innovation Award, the Burroughs Wellcome Career Award, and a Searle Scholarship. He was also named to the 40-Under-40 list by ''Crain’s Chicago Business'' magazine, Forbes China 100 Most Influential Chinese Worldwide, and PharmaVoice 100 Top Industry Leaders. Lahn received his B.A. in General Biology from Harvard University and his Ph.D. from the Massachusetts Institute of Technology in the lab of David C. Page. From 2000 to 2012, Lahn was a Howard Hughes Medical Inst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Archaic Human Admixture With Modern Humans
Interbreeding between archaic and modern humans occurred during the Middle Paleolithic and early Upper Paleolithic. The interbreeding happened in several independent events that included Neanderthals and Denisovans, as well as several unidentified hominins. In Europe, Asia and North Africa, interbreeding between archaic humans and modern humans took place several times. The introgression events into modern humans are estimated to have happened about 47,000–65,000 years ago with Neanderthals and about 44,000–54,000 years ago with Denisovans. Neanderthal-derived DNA has been found in the genomes of most contemporary populations, varying noticeably by region. It accounts for 1–4% of modern genomes for people outside Sub-Saharan Africa, although estimates vary, and either none or up to 0.3% for those in Sub-Saharan Africa. Cushitic and Semitic speaking populations from the Horn of Africa (such as Ethiopians), who derive a large portion of their ancestry from West Eurasian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
BRCT Domain
BRCA1 C Terminus (BRCT) domain is a family of evolutionarily related proteins. It is named after the C-terminal domain of BRCA1, a DNA-repair protein that serves as a marker of breast cancer susceptibility. The BRCT domain is found predominantly in proteins involved in cell cycle checkpoint functions responsive to DNA damage, for example as found in the breast cancer DNA-repair protein BRCA1. The domain is an approximately 100 amino acid tandem repeat, which appears to act as a phospho-protein binding domain. Examples Human proteins containing this domain include: * BARD1; BRCA1 * CTDP1; TDT or DNTT * ECT2 * LIG4 * MCPH1; MDC1 * NBN * PARP1; PARP4; PAXIP1; PES1 * REV1; RFC1; TOPBP1 DNA topoisomerase 2-binding protein 1 (TOPBP1) is a scaffold protein that in humans is encoded by the ''TOPBP1'' gene. TOPBP1 was first identified as a protein binding partner of DNA TOP2B, topoisomerase-IIβ by a Two-hybrid screening, yeast 2- ...; TP53BP1; XRCC1 References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Neuron
A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural network in the nervous system. They are located in the nervous system and help to receive and conduct impulses. Neurons communicate with other cells via synapses, which are specialized connections that commonly use minute amounts of chemical neurotransmitters to pass the electric signal from the presynaptic neuron to the target cell through the synaptic gap. Neurons are the main components of nervous tissue in all Animalia, animals except sponges and placozoans. Plants and fungi do not have nerve cells. Molecular evidence suggests that the ability to generate electric signals first appeared in evolution some 700 to 800 million years ago, during the Tonian period. Predecessors of neurons were the peptidergic secretory cells. They eventually ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Upstream And Downstream (DNA)
In molecular biology and genetics, upstream and downstream both refer to relative positions of genetic code in DNA or RNA. Each strand of DNA or RNA has a 5' end and a 3' end, so named for the carbon position on the deoxyribose (or ribose) ring. By convention, upstream and downstream relate to the 5' to 3' direction respectively in which RNA transcription takes place. Upstream is toward the 5' end of the RNA molecule, and downstream is toward the 3' end. When considering double-stranded DNA, upstream is toward the 5' end of the coding strand for the gene in question and downstream is toward the 3' end. Due to the anti-parallel nature of DNA, this means the 3' end of the template strand is upstream of the gene and the 5' end is downstream. Some genes on the same DNA molecule may be transcribed in opposite directions. This means the upstream and downstream areas of the molecule may change depending on which gene is used as the reference. The terms upstream and downstream are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Genome-wide Association Study
In genomics, a genome-wide association study (GWA study, or GWAS), is an observational study of a genome-wide set of Single-nucleotide polymorphism, genetic variants in different individuals to see if any variant is associated with a trait. GWA studies typically focus on associations between single-nucleotide polymorphisms (SNPs) and traits like major human diseases, but can equally be applied to any other genetic variants and any other organisms. When applied to human data, GWA studies compare the DNA of participants having varying phenotypes for a particular trait or disease. These participants may be people with a disease (cases) and similar people without the disease (controls), or they may be people with different phenotypes for a particular trait, for example blood pressure. This approach is known as phenotype-first, in which the participants are classified first by their clinical manifestation(s), as opposed to Genotype-first approach, genotype-first. Each person gives a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Richard Lewontin
Richard Charles Lewontin (March 29, 1929 – July 4, 2021) was an American evolutionary biologist, mathematician, geneticist, and social commentator. A leader in developing the mathematical basis of population genetics and evolutionary theory, he applied techniques from molecular biology, such as gel electrophoresis, to questions of genetic variation and evolution. In a pair of seminal 1966 papers co-authored with J. L. Hubby in the journal ''Genetics'', Lewontin helped set the stage for the modern field of molecular evolution. In 1979, he and Stephen Jay Gould introduced the term "spandrel" into evolutionary theory. From 1973 to 1998, he held an endowed chair in zoology and biology at Harvard University, and from 2003 until his death in 2021 he was a research professor there. From a sociological perspective, Lewontin strongly opposed genetic determinism and neodarwinism as expressed in the fields of sociobiology and evolutionary psychology. Previously, as a member of Scie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
John Derbyshire
John Derbyshire (born 3 June 1945) is an American journalist and political commentator. He was one of the last paleoconservatives at the ''National Review'', until he was fired in 2012 for writing an article for '' Taki's Magazine'' that was widely viewed as racist. Since 2012 he has written for white nationalist website VDARE. In the article that caused his firing, Derbyshire suggested that white and East Asian parents should talk to their children about the threats posed to their safety by black people. He also recommended that parents tell their children not to live in predominantly black communities. He included the line "If planning a trip to a beach or amusement park at some date, find out whether it is likely to be swamped with blacks on that date." He has also written for the '' New English Review''. His columns cover political-cultural topics, including immigration, China, history, mathematics, and race. Derbyshire's 1996 novel about Chinese American immigrants, ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Neanderthal
Neanderthals ( ; ''Homo neanderthalensis'' or sometimes ''H. sapiens neanderthalensis'') are an extinction, extinct group of archaic humans who inhabited Europe and Western and Central Asia during the Middle Pleistocene, Middle to Late Pleistocene. Neanderthal extinction occurred roughly 40,000 years ago with the immigration of modern humans (Cro-Magnons), but Neanderthals in Gibraltar may have persisted for thousands of years longer. The first recognised Neanderthal fossil, Neanderthal 1, was discovered in 1856 in the Neander Valley, Germany. At first, Neanderthal 1 was considered to be one of the racial hierarchy, lower races in accord with historical race concepts. As more fossils were discovered through the early 20th century, Neanderthals became characterised most especially by Marcellin Boule as a unique species of underdeveloped human. By the mid-20th century, human evolution was described as progressing from an apelike ancestor, through a "Neanderthal phase", ending ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Chromosome
A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most important of these proteins are the histones. Aided by chaperone proteins, the histones bind to and condense the DNA molecule to maintain its integrity. These eukaryotic chromosomes display a complex three-dimensional structure that has a significant role in transcriptional regulation. Normally, chromosomes are visible under a light microscope only during the metaphase of cell division, where all chromosomes are aligned in the center of the cell in their condensed form. Before this stage occurs, each chromosome is duplicated ( S phase), and the two copies are joined by a centromere—resulting in either an X-shaped structure if the centromere is located equatorially, or a two-armed structure if the centromere is located distally; the jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Tonal Language
Tone is the use of pitch in language to distinguish lexical or grammatical meaning—that is, to distinguish or to inflect words. All oral languages use pitch to express emotional and other para-linguistic information and to convey emphasis, contrast and other such features in what is called intonation, but not all languages use tones to distinguish words or their inflections, analogously to consonants and vowels. Languages that have this feature are called tonal languages; the distinctive tone patterns of such a language are sometimes called tonemes, by analogy with ''phoneme''. Tonal languages are common in East and Southeast Asia, Africa, the Americas, and the Pacific. Tonal languages are different from pitch-accent languages in that tonal languages can have each syllable with an independent tone whilst pitch-accent languages may have one syllable in a word or morpheme that is more prominent than the others. Mechanics Most languages use pitch as intonation to convey ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
