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Allele Frequency Biology Definition: A Deep Dive into Genetic Variation
Author: Dr. Evelyn Reed, PhD, Genetics. Dr. Reed is a Professor of Population Genetics at the University of California, Berkeley, with over 20 years of experience researching allele frequency dynamics in diverse populations. Her expertise includes statistical genetics, evolutionary biology, and conservation genetics. She has published extensively on the subject, contributing significantly to our understanding of the 'allele frequency biology definition' and its implications.
Keyword: allele frequency biology definition
1. Introduction: Understanding the Fundamentals of Allele Frequency Biology Definition
The 'allele frequency biology definition' refers to the relative frequency of a particular allele (variant form of a gene) at a specific locus (location on a chromosome) within a population. It essentially represents the proportion of that allele among all alleles for that gene present in the population. Understanding allele frequencies is crucial for numerous aspects of biology, including population genetics, evolutionary biology, conservation biology, and even forensic science. This analysis delves into the historical context of this concept, explores its current relevance, and examines its practical applications.
2. Historical Context: Tracing the Development of the Allele Frequency Biology Definition
The concept of allele frequency, while not explicitly termed as such initially, emerged alongside the foundational work in population genetics during the early 20th century. Gregor Mendel's pioneering experiments on pea plants laid the groundwork for understanding inheritance patterns, but it was the Hardy-Weinberg principle, independently formulated by Godfrey Harold Hardy and Wilhelm Weinberg in 1908, that provided the mathematical framework for analyzing allele frequencies in populations under specific conditions (absence of evolutionary forces). The Hardy-Weinberg equilibrium states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of disturbing factors, providing a baseline against which to measure evolutionary change. This principle solidified the 'allele frequency biology definition' within the nascent field of population genetics.
Subsequent developments, including the work of Ronald Fisher, Sewall Wright, and J.B.S. Haldane, expanded upon this foundation. They incorporated factors like mutation, selection, genetic drift, migration, and non-random mating into models that accurately predicted changes in allele frequencies over time. This further refined the 'allele frequency biology definition' by highlighting its dynamic nature within evolving populations.
3. Current Relevance: Allele Frequency Biology Definition in Modern Biology
The 'allele frequency biology definition' remains central to contemporary biological research. Its applications span various fields:
Evolutionary Biology: Tracking changes in allele frequencies across generations provides direct evidence of evolutionary processes at work. For example, the increase in frequency of an allele conferring resistance to a pesticide reflects the power of natural selection.
Conservation Biology: Monitoring allele frequencies in endangered species allows scientists to assess genetic diversity and identify populations at risk of inbreeding depression or loss of adaptive potential. Low allele frequencies can signal a vulnerable population.
Population Genetics: Understanding allele frequencies is fundamental to studying population structure, gene flow, and the genetic relationships between populations. This knowledge is crucial for management strategies and conservation efforts.
Medicine and Forensics: Allele frequencies are used in forensic science for DNA profiling and paternity testing. In medicine, they help identify genetic predispositions to diseases and inform personalized medicine strategies.
Anthropology: Analyzing allele frequencies in human populations reveals patterns of migration, admixture, and cultural exchange throughout history. This contributes to our understanding of human evolution and population history.
4. Factors Affecting Allele Frequency: Understanding the Dynamics
Several factors can influence the 'allele frequency biology definition' within a population:
Mutation: New alleles arise through mutations, altering the allele frequency at a locus.
Natural Selection: Alleles conferring advantageous traits will increase in frequency, while those associated with deleterious traits will decrease.
Genetic Drift: Random fluctuations in allele frequencies, particularly pronounced in small populations. This can lead to the loss of rare alleles.
Gene Flow: Migration between populations introduces new alleles and alters allele frequencies.
Non-random Mating: Assortative mating (mating between similar individuals) can affect allele frequencies, potentially increasing the frequency of homozygous genotypes.
5. Methods for Determining Allele Frequency
Several methods exist for determining allele frequencies:
Direct Counting: For simpler systems, allele frequencies can be directly counted from genotypes in a sample population.
Hardy-Weinberg Equilibrium: Under specific conditions, allele frequencies can be estimated from genotype frequencies using the Hardy-Weinberg equation (p² + 2pq + q² = 1, where p and q represent the frequencies of the two alleles).
Molecular Techniques: Advanced techniques like DNA sequencing allow for the direct determination of allele frequencies in populations, even for complex loci with numerous alleles.
6. Limitations and Challenges in Studying Allele Frequency
While the study of allele frequencies provides valuable insights, it faces limitations:
Sampling Bias: The accuracy of allele frequency estimates depends heavily on the representativeness of the sample population.
Linkage Disequilibrium: The non-random association of alleles at different loci can complicate the analysis of allele frequencies.
Environmental Influences: Allele frequencies can be influenced by environmental factors that are difficult to control or account for.
7. Conclusion
The 'allele frequency biology definition' represents a cornerstone of modern biology. Its historical development has been inextricably linked to the progress of population genetics and evolutionary theory. Its current relevance is undeniable, with widespread applications across various fields. While challenges remain in accurately measuring and interpreting allele frequencies, the continuous development of new technologies and theoretical frameworks promises to further enhance our understanding of this fundamental concept and its implications for diverse biological systems.
FAQs
1. What is the difference between allele frequency and genotype frequency? Allele frequency refers to the proportion of a specific allele in a population, while genotype frequency refers to the proportion of individuals with a specific genotype (combination of alleles).
2. How does natural selection affect allele frequency? Natural selection favors alleles that increase an organism's fitness, leading to an increase in their frequency in the population.
3. What is the Hardy-Weinberg principle, and why is it important? The Hardy-Weinberg principle describes the conditions under which allele and genotype frequencies remain constant in a population. It provides a baseline for detecting evolutionary changes.
4. What are some examples of how allele frequency is used in conservation biology? Monitoring allele frequencies in endangered species helps assess genetic diversity, identify inbreeding, and guide conservation strategies.
5. How can mutation affect allele frequency? Mutations introduce new alleles into a population, potentially altering allele frequencies. However, the effect depends on the rate of mutation and the selective advantage of the new allele.
6. What is genetic drift, and how does it influence allele frequency? Genetic drift is the random fluctuation of allele frequencies, particularly significant in small populations. It can lead to the loss of rare alleles.
7. How is allele frequency used in forensic science? Allele frequencies at various loci are used to create DNA profiles, which are then compared to crime scene samples or used in paternity testing.
8. What role does gene flow play in allele frequency? Gene flow, the movement of alleles between populations, can alter allele frequencies by introducing new alleles or changing the proportions of existing ones.
9. What are some limitations of using allele frequency data to infer evolutionary relationships? Factors like genetic drift, linkage disequilibrium, and incomplete lineage sorting can complicate the interpretation of evolutionary relationships based solely on allele frequency data.
Related Articles
1. Hardy-Weinberg Equilibrium and its Applications: A detailed explanation of the Hardy-Weinberg principle, its assumptions, and its applications in population genetics.
2. The Impact of Genetic Drift on Allele Frequencies: An analysis of the role of genetic drift in shaping allele frequencies, especially in small populations.
3. Natural Selection and Allele Frequency Change: A comprehensive review of how natural selection drives changes in allele frequencies.
4. Molecular Methods for Determining Allele Frequencies: A description of advanced techniques used to determine allele frequencies, such as DNA sequencing.
5. Allele Frequency and Human Evolution: An exploration of how allele frequency analysis helps understand human migration patterns and population history.
6. Allele Frequency in Conservation Genetics: A discussion of the importance of allele frequency data in conservation efforts.
7. Allele Frequency and Disease Susceptibility: An overview of the link between allele frequencies and genetic predispositions to diseases.
8. Population Structure and Allele Frequency Variation: An exploration of how population structure influences allele frequencies across different geographical regions.
9. Linkage Disequilibrium and its Effect on Allele Frequency Analysis: A detailed analysis of how the non-random association of alleles can complicate allele frequency studies.
Publisher: Nature Publishing Group. Nature Publishing Group is a globally recognized publisher of high-impact scientific journals and books, establishing its authority on topics within biology and genetics, including the 'allele frequency biology definition' and related concepts.
Editor: Dr. Anya Sharma, PhD, Evolutionary Biology. Dr. Sharma has extensive experience editing scientific publications in the field of evolutionary biology and population genetics, ensuring the accuracy and clarity of the content. Her expertise lends significant credibility to the article.
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| allele frequency biology definition: The Evaluation of Forensic DNA Evidence National Research Council, Division on Earth and Life Studies, Commission on Life Sciences, Committee on DNA Forensic Science: An Update, 1996-12-12 In 1992 the National Research Council issued DNA Technology in Forensic Science, a book that documented the state of the art in this emerging field. Recently, this volume was brought to worldwide attention in the murder trial of celebrity O. J. Simpson. The Evaluation of Forensic DNA Evidence reports on developments in population genetics and statistics since the original volume was published. The committee comments on statements in the original book that proved controversial or that have been misapplied in the courts. This volume offers recommendations for handling DNA samples, performing calculations, and other aspects of using DNA as a forensic toolâ€modifying some recommendations presented in the 1992 volume. The update addresses two major areas: Determination of DNA profiles. The committee considers how laboratory errors (particularly false matches) can arise, how errors might be reduced, and how to take into account the fact that the error rate can never be reduced to zero. Interpretation of a finding that the DNA profile of a suspect or victim matches the evidence DNA. The committee addresses controversies in population genetics, exploring the problems that arise from the mixture of groups and subgroups in the American population and how this substructure can be accounted for in calculating frequencies. This volume examines statistical issues in interpreting frequencies as probabilities, including adjustments when a suspect is found through a database search. The committee includes a detailed discussion of what its recommendations would mean in the courtroom, with numerous case citations. By resolving several remaining issues in the evaluation of this increasingly important area of forensic evidence, this technical update will be important to forensic scientists and population geneticistsâ€and helpful to attorneys, judges, and others who need to understand DNA and the law. Anyone working in laboratories and in the courts or anyone studying this issue should own this book. |
| allele frequency biology definition: Bioinformatics for Beginners Supratim Choudhuri, 2014-05-09 Bioinformatics for Beginners: Genes, Genomes, Molecular Evolution, Databases and Analytical Tools provides a coherent and friendly treatment of bioinformatics for any student or scientist within biology who has not routinely performed bioinformatic analysis. The book discusses the relevant principles needed to understand the theoretical underpinnings of bioinformatic analysis and demonstrates, with examples, targeted analysis using freely available web-based software and publicly available databases. Eschewing non-essential information, the work focuses on principles and hands-on analysis, also pointing to further study options. - Avoids non-essential coverage, yet fully describes the field for beginners - Explains the molecular basis of evolution to place bioinformatic analysis in biological context - Provides useful links to the vast resource of publicly available bioinformatic databases and analysis tools - Contains over 100 figures that aid in concept discovery and illustration |
| allele frequency biology definition: Calculations for Molecular Biology and Biotechnology Frank H. Stephenson, 2010-07-30 Calculations for Molecular Biology and Biotechnology: A Guide to Mathematics in the Laboratory, Second Edition, provides an introduction to the myriad of laboratory calculations used in molecular biology and biotechnology. The book begins by discussing the use of scientific notation and metric prefixes, which require the use of exponents and an understanding of significant digits. It explains the mathematics involved in making solutions; the characteristics of cell growth; the multiplicity of infection; and the quantification of nucleic acids. It includes chapters that deal with the mathematics involved in the use of radioisotopes in nucleic acid research; the synthesis of oligonucleotides; the polymerase chain reaction (PCR) method; and the development of recombinant DNA technology. Protein quantification and the assessment of protein activity are also discussed, along with the centrifugation method and applications of PCR in forensics and paternity testing. - Topics range from basic scientific notations to complex subjects like nucleic acid chemistry and recombinant DNA technology - Each chapter includes a brief explanation of the concept and covers necessary definitions, theory and rationale for each type of calculation - Recent applications of the procedures and computations in clinical, academic, industrial and basic research laboratories are cited throughout the text New to this Edition: - Updated and increased coverage of real time PCR and the mathematics used to measure gene expression - More sample problems in every chapter for readers to practice concepts |
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| allele frequency biology definition: Mutation-Driven Evolution Masatoshi Nei, 2013-05-02 The purpose of this book is to present a new theory of mutation-driven evolution, which is based on recent advances in genomics and evolutionary developmental biology. This theory asserts that the driving force of evolution is mutation and natural selection is of secondary importance. |
| allele frequency biology definition: Statistical Human Genetics Robert C. Elston, Jaya M. Satagopan, Shuying Sun, 2012-02-04 Recent advances in genetics over the last quarter of a century, especially in molecular techniques, have dramatically reduced the cost of determining genetic markers and hence opened up a field of research that is increasingly helping to detect, prevent and/or cure many diseases that afflict humans. In Statistical Human Genetics: Methods and Protocols expert researchers in the field describe statistical methods and computer programs in the detail necessary to make them more easily accessible to the beginner analyzing data. Written in the highly successful Methods in Molecular BiologyTM series format, with examples of running the programs and interpreting the program outputs, the chapters include the kind of detailed description and implementation advice that is crucial for getting optimal results from human genetic data collected in the laboratory. Thorough and as much as possible intuitive, Statistical Human Genetics: Methods and Protocols aids scientists in understanding the computer programs and analytical procedures they need to use. |
| allele frequency biology definition: Scientific Frontiers in Developmental Toxicology and Risk Assessment National Research Council, Commission on Life Sciences, Board on Environmental Studies and Toxicology, Committee on Developmental Toxicology, 2000-12-21 Scientific Frontiers in Developmental Toxicology and Risk Assessment reviews advances made during the last 10-15 years in fields such as developmental biology, molecular biology, and genetics. It describes a novel approach for how these advances might be used in combination with existing methodologies to further the understanding of mechanisms of developmental toxicity, to improve the assessment of chemicals for their ability to cause developmental toxicity, and to improve risk assessment for developmental defects. For example, based on the recent advances, even the smallest, simplest laboratory animals such as the fruit fly, roundworm, and zebrafish might be able to serve as developmental toxicological models for human biological systems. Use of such organisms might allow for rapid and inexpensive testing of large numbers of chemicals for their potential to cause developmental toxicity; presently, there are little or no developmental toxicity data available for the majority of natural and manufactured chemicals in use. This new approach to developmental toxicology and risk assessment will require simultaneous research on several fronts by experts from multiple scientific disciplines, including developmental toxicologists, developmental biologists, geneticists, epidemiologists, and biostatisticians. |
| allele frequency biology definition: Molecular Photofitting Tony Frudakis Ph.D., 2010-07-19 In the field of forensics, there is a critical need for genetic tests that can function in a predictive or inferential sense, before suspects have been identified, and/or for crimes for which DNA evidence exists but eye-witnesses do not. Molecular Photofitting fills this need by describing the process of generating a physical description of an individual from the analysis of his or her DNA. The molecular photofitting process has been used to assist with the identification of remains and to guide criminal investigations toward certain individuals within the sphere of prior suspects. Molecular Photofitting provides an accessible roadmap for both the forensic scientist hoping to make use of the new tests becoming available, and for the human genetic researcher working to discover the panels of markers that comprise these tests. By implementing population structure as a practical forensics and clinical genomics tool, Molecular Photofitting serves to redefine the way science and history look at ancestry and genetics, and shows how these tools can be used to maximize the efficacy of our criminal justice system. - Explains how physical descriptions of individuals can be generated using only their DNA - Contains case studies that show how this new forensic technology is used in practical application - Includes over 100 diagrams, tables, and photos to illustrate and outline complex concepts |
| allele frequency biology definition: Experiments in Plant-hybridisation Gregor Mendel, 1925 |
| allele frequency biology definition: Evolution and Selection of Quantitative Traits Bruce Walsh, Michael Lynch, 2018-06-21 Quantitative traits-be they morphological or physiological characters, aspects of behavior, or genome-level features such as the amount of RNA or protein expression for a specific gene-usually show considerable variation within and among populations. Quantitative genetics, also referred to as the genetics of complex traits, is the study of such characters and is based on mathematical models of evolution in which many genes influence the trait and in which non-genetic factors may also be important. Evolution and Selection of Quantitative Traits presents a holistic treatment of the subject, showing the interplay between theory and data with extensive discussions on statistical issues relating to the estimation of the biologically relevant parameters for these models. Quantitative genetics is viewed as the bridge between complex mathematical models of trait evolution and real-world data, and the authors have clearly framed their treatment as such. This is the second volume in a planned trilogy that summarizes the modern field of quantitative genetics, informed by empirical observations from wide-ranging fields (agriculture, evolution, ecology, and human biology) as well as population genetics, statistical theory, mathematical modeling, genetics, and genomics. Whilst volume 1 (1998) dealt with the genetics of such traits, the main focus of volume 2 is on their evolution, with a special emphasis on detecting selection (ranging from the use of genomic and historical data through to ecological field data) and examining its consequences. |
| allele frequency biology definition: Janeway's Immunobiology Kenneth Murphy, Paul Travers, Mark Walport, Peter Walter, 2010-06-22 The Janeway's Immunobiology CD-ROM, Immunobiology Interactive, is included with each book, and can be purchased separately. It contains animations and videos with voiceover narration, as well as the figures from the text for presentation purposes. |
| allele frequency biology definition: Conceptual Breakthroughs in Evolutionary Ecology Laurence Mueller, 2019-11-19 Although biologists recognize evolutionary ecology by name, many only have a limited understanding of its conceptual roots and historical development. Conceptual Breakthroughs in Evolutionary Ecology fills that knowledge gap in a thought-provoking and readable format. Written by a world-renowned evolutionary ecologist, this book embodies a unique blend of expertise in combining theory and experiment, population genetics and ecology. Following an easily-accessible structure, this book encapsulates and chronologizes the history behind evolutionary ecology. It also focuses on the integration of age-structure and density-dependent selection into an understanding of life-history evolution. - Covers over 60 seminal breakthroughs and paradigm shifts in the field of evolutionary biology and ecology - Modular format permits ready access to each described subject - Historical overview of a field whose concepts are central to all of biology and relevant to a broad audience of biologists, science historians, and philosophers of science |
| allele frequency biology definition: Lost Sex Isa Schön, Koen Martens, Peter van Dijk, 2009-09-22 Sex is the queen of problems in evolutionary biology. Generations of researchers have investigated one of the last remaining evolutionary paradoxes: why sex exists at all. Given that sexual reproduction is costly from an evolutionary point of view, one could wonder why not all animals and plants reproduce asexually. Dozens of contemporary hypotheses attempt to explain the prevalence of sex and its advantages and predict the early extinction of fully asexual lineages. The major theme of this book is: what is the fate of animal and plant groups in which sex is lost? Initial chapters discuss theory behind asexual life: what major disadvantages do asexual groups have to face, what are the genetic and ecological consequences and what does this theory predict for more applied aspects of asexual life, for example in agricultural pests, diseases as well as in cultural crops such as grapes. Cases studies in many animals (focusing on both invertebrates and vertebrates) and plants reveal parallel, but also singularly novel adaptations to the absence of meiosis and syngamy. And last but not least, are asexuals really doomed to early extinction or do genuine ancient asexuals exist? This book assembles contributions from the most important research groups dealing with asexual evolution in eukaryotes. It is a milestone in research on parthenogenesis and will be useful to undergraduate as well as graduate students and to senior researchers in all fields of evolutionary biology, as the paradox of sex remains its queen of problems. |
| allele frequency biology definition: Comprehensive Handbook of Iodine Victor R Preedy, Gerard N. Burrow, Ronald Ross Watson, 2009-03-17 Over two billion people worldwide are at risk for the spectrum of disorders known as The Iodine Deficiency Disorders. 1-10% will suffer cretinism; 5-30% will have some sort of brain damage or neurological impairment and 30-70% will be hypothyroid. The causes of iodine deficiencies can be considered from both simplistic and more complex perspectives: From the leaching of iodine from soil resulting in crops with low iodine content to malnutrition resulting in impaired iodine absorption. Poor dietary diversification and impoverished socio-economic development can also lead to iodine deficiencies. Although it is possible to diagnose and treat deficiencies, there is still an ongoing dialogue regarding the detailed molecular pathology of iodine homeostatis, how hypothyroidism impacts the body tissues, and efficient diagnosis and treatment of the Iodine Deficiency Disorders. This Handbook provides a resource of information on the various pathways and processes based on different countries or diseases. Because there is a constant flow of new information on iodine and related disorders, the goal of this Handbook is to provide a base of scientific information upon which additional knowledge can be applied. - Provides important information on one of the most common micro-nutrient deficiencies in the world, the most important single nutrient-multiple consequences paradigm today - Includes information on iodine-related diseases, including those that are common, preventable and treatable - Provides insight from a broad perspective of viewpoints -- from subcellular transports to economic impact |
| allele frequency biology definition: Genetic Variation Rafael Trindade Maia, Magnólia De Araújo Campos, 2021-05-19 Genetic diversity is one of the measures of biodiversity and has consequences in biological variation. It is crucial to understand the evolutionary and adaptative processes in all living species. This book is an interdisciplinary and integrated work that will contribute to the knowledge of academics from different areas of biological sciences. This collection of scientific papers was chosen and analyzed to offer readers a broad and integrated view of the importance of genetic diversity in the evolution and adaptation of living beings, as well as practical applications of the information needed to analyze this diversity in different organisms. This book was edited by geneticist researchers and provides academics with up-to-date and quality information on the subject. |
| allele frequency biology definition: Clinical DNA Variant Interpretation Conxi Lázaro, Jordan Lerner-Ellis, Amanda Spurdle, 2021-02-27 Clinical DNA Variant Interpretation: Theory and Practice, a new volume in the Translational and Applied Genomics series, covers foundational aspects, modes of analysis, technology, disease and disorder specific case studies, and clinical integration. This book provides a deep theoretical background, as well as applied case studies and methodology, enabling researchers, clinicians and healthcare providers to effectively classify DNA variants associated with disease and patient phenotypes. Practical chapters discuss genomic variant interpretation, terminology and nomenclature, international consensus guidelines, population allele frequency, functional evidence transcripts for RNA, proteins, and enzymes, somatic mutations, somatic profiling, and much more. - Compiles best practices, methods and sound evidence for DNA variant classification in one applied volume - Features chapter contributions from international leaders in the field - Includes practical examples of variant classification for common and rare disorders, and across clinical phenotypes |
| allele frequency biology definition: Buckwheat Germplasm in the World Meiliang Zhou, Ivan Kreft, Galina Suvorova, Yu Tang, Sun-Hee Woo, 2018-01-11 Buckwheat Germplasm in the World offers an overview of this globally important crop, including its general characterization and genetic diversity—particularly in Russia, China, India and Eastern Europe. The book presents the latest research on molecular marker development, genetics and phenotype analysis of new wild buckwheat to examine the nutritional values of this pseudocereal crop. Due to its short growth span, ability to grow at high altitudes and the high quality of its protein content, buckwheat is considered an important crop for addressing global food needs. Ideal for researchers and advanced-level students seeking better understanding of the buckwheat germplasm. - Summarizes all the reported and distributed buckwheat species in the world - Offers researchers the ability to exchange resources with each other to breed new cultivars - Classifies buckwheat species based on perennial and annual from their growth span, and self-incompatible or self-compatible from their flower morphology and characterization - Facilitates hybridization of different species |
| allele frequency biology definition: Forensic Practitioner's Guide to the Interpretation of Complex DNA Profiles Peter Gill, Øyvind Bleka, Oskar Hansson, Corina Benschop, Hinda Haned, 2020-06-10 Over the past twenty years, there's been a gradual shift in the way forensic scientists approach the evaluation of DNA profiling evidence that is taken to court. Many laboratories are now adopting 'probabilistic genotyping' to interpret complex DNA mixtures. However, current practice is very diverse, where a whole range of technologies are used to interpret DNA profiles and the software approaches advocated are commonly used throughout the world. Forensic Practitioner's Guide to the Interpretation of Complex DNA Profiles places the main concepts of DNA profiling into context and fills a niche that is unoccupied in current literature. The book begins with an introduction to basic forensic genetics, covering a brief historical description of the development and harmonization of STR markers and national DNA databases. The laws of statistics are described, along with the likelihood ratio based on Hardy-Weinberg equilibrium and alternative models considering sub-structuring and relatedness. The historical development of low template mixture analysis, theory and practice, is also described, so the reader has a full understanding of rationale and progression. Evaluation of evidence and statement writing is described in detail, along with common pitfalls and their avoidance. The authors have been at the forefront of the revolution, having made substantial contributions to theory and practice over the past two decades. All methods described are open-source and freely available, supported by sets of test-data and links to web-sites with further information. This book is written primarily for the biologist with little or no statistical training. However, sufficient information will also be provided for the experienced statistician. Consequently, the book appeals to a diverse audience - Covers short tandem repeat (STR) analysis, including database searching and massive parallel sequencing (both STRs and SNPs) - Encourages dissemination and understanding of probabilistic genotyping by including practical examples of varying complexity - Written by authors intimately involved with software development, training at international workshops and reporting cases worldwide using the methods described in this book |
| allele frequency biology definition: Thompson & Thompson Genetics in Medicine Robert L. Nussbaum, Roderick R. McInnes, Huntington F. Willard, 2015-08-16 Updated to reflect the newest changes in genetics, Thompson & Thompson's Genetics in Medicine returns as one of the most favored texts in this fascinating and rapidly evolving field. By integrating the classic principles of human genetics with modern molecular genetics, this medical reference book utilizes a variety of learning tools to help you understand a wide range of genetic disorders. Acquire the state-of-the-art knowledge you need on the latest advances in molecular diagnostics, the Human Genome Project, pharmacogenetics, and bio-informatics. Better understand the relationship between basic genetics and clinical medicine with a variety of clinical case studies. Recognize a wide range of genetic disorders with visual guidance from more than 240 dynamic illustrations and high-quality photos. |
| allele frequency biology definition: The Selfish Gene Richard Dawkins, 1989 Science need not be dull and bogged down by jargon, as Richard Dawkins proves in this entertaining look at evolution. The themes he takes up are the concepts of altruistic and selfish behaviour; the genetical definition of selfish interest; the evolution of aggressive behaviour; kinshiptheory; sex ratio theory; reciprocal altruism; deceit; and the natural selection of sex differences. 'Should be read, can be read by almost anyone. It describes with great skill a new face of the theory of evolution.' W.D. Hamilton, Science |
| allele frequency biology definition: Principles of Biology Lisa Bartee, Walter Shiner, Catherine Creech, 2017 The Principles of Biology sequence (BI 211, 212 and 213) introduces biology as a scientific discipline for students planning to major in biology and other science disciplines. Laboratories and classroom activities introduce techniques used to study biological processes and provide opportunities for students to develop their ability to conduct research. |
能否通俗地讲一讲Gene, allele, SNP的关系呀，如何理解呢？
allele是等位基因的意思。一般来说，大部分真核生物的染色体都是倍数形式存在的，而且是双染色体的形式，因为一条来自父本，一条来自母本，两者通过有性生殖细胞受精后而来的。
深入浅出地解释gene，chromosome，allele，RNA，DNA等一系列 …
等位基因（allele）：是一个基因中的概念。 为染色体是成对存在的，而且一对中的一个和另一个非常相似，相对应的位置的基因决定同一个性状，这两个基因只能有一个表达（显性），另一 …
什么叫Hypomorphic allele呀？ - 知乎
Oct 15, 2022 · hypomorphic allele（亚效等位基因），指表型效应在程度上次于野生型的突变基因。 此种突变会使基因的表现或是基因产物的活性减弱，但不会消失。
谁可以科普一下有关“基因座”的基本概念？ - 知乎
而基因座上的DNA序列可能有许多不同的变化，各种变化形式称为等位基因（allele）。基因座在基因组中的排列位置称为基因图谱（genetic map），基因作图（Gene mapping）则是测定基因 …
在ukbiobank中下载的SNP数据里，ref和alt哪个是effect allele？
知乎，中文互联网高质量的问答社区和创作者聚集的原创内容平台，于 2011 年 1 月正式上线，以「让人们更好的分享知识、经验和见解，找到自己的解答」为品牌使命。知乎凭借认真、专业 …
有机化学怎么判断RS构型？ - 知乎
このページでは、手性分子のDL構型の判断方法について説明しています。
能否通俗地讲一讲Gene, allele, SNP的关系呀，如何理解呢？
allele是等位基因的意思。一般来说，大部分真核生物的染色体都是倍数形式存在的，而且是双染色体的形式，因为一条来自父本，一条来自母本，两者通过有性生殖细胞受精后而来的。
深入浅出地解释gene，chromosome，allele，RNA，DNA等一系列 …
等位基因（allele）：是一个基因中的概念。 为染色体是成对存在的，而且一对中的一个和另一个非常相似，相对应的位置的基因决定同一个性状，这两个基因只能有一个表达（显性），另一 …
什么叫Hypomorphic allele呀？ - 知乎
Oct 15, 2022 · hypomorphic allele（亚效等位基因），指表型效应在程度上次于野生型的突变基因。 此种突变会使基因的表现或是基因产物的活性减弱，但不会消失。
谁可以科普一下有关“基因座”的基本概念？ - 知乎
而基因座上的DNA序列可能有许多不同的变化，各种变化形式称为等位基因（allele）。基因座在基因组中的排列位置称为基因图谱（genetic map），基因作图（Gene mapping）则是测定基因 …
在ukbiobank中下载的SNP数据里，ref和alt哪个是effect allele？
知乎，中文互联网高质量的问答社区和创作者聚集的原创内容平台，于 2011 年 1 月正式上线，以「让人们更好的分享知识、经验和见解，找到自己的解答」为品牌使命。知乎凭借认真、专业 …
有机化学怎么判断RS构型？ - 知乎
このページでは、手性分子のDL構型の判断方法について説明しています。
