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Author (up) Bailey, A.; Le Couteur, A.; Gottesman, I.; Bolton, P.; Simonoff, E.; Yuzda, E.; Rutter, M. file  url
  Title Autism as a strongly genetic disorder: evidence from a British twin study Type Journal Article
  Year 1995 Publication Psychological Medicine Abbreviated Journal Psychol Med  
  Volume 25 Issue 1 Pages 63-77  
  Keywords Abnormalities, Multiple/diagnosis/genetics/psychology; Adolescent; Adult; Autistic Disorder/diagnosis/*genetics/psychology; Child; Child, Preschool; Diseases in Twins/*genetics/psychology; Female; Follow-Up Studies; Great Britain; Humans; Infant; Infant, Newborn; Intelligence/genetics; Male; Models, Genetic; Personality Assessment; Pregnancy; Prenatal Exposure Delayed Effects; Risk Factors; Social Adjustment; Social Environment; Twins, Dizygotic/genetics/psychology; Twins, Monozygotic/genetics/psychology  
  Abstract Two previous epidemiological studies of autistic twins suggested that autism was predominantly genetically determined, although the findings with regard to a broader phenotype of cognitive, and possibly social, abnormalities were contradictory. Obstetric and perinatal hazards were also invoked as environmentally determined aetiological factors. The first British twin sample has been re-examined and a second total population sample of autistic twins recruited. In the combined sample 60% of monozygotic (MZ) pairs were concordant for autism versus no dizygotic (DZ) pairs; 92% of MZ pairs were concordant for a broader spectrum of related cognitive or social abnormalities versus 10% of DZ pairs. The findings indicate that autism is under a high degree of genetic control and suggest the involvement of multiple genetic loci. Obstetric hazards usually appear to be consequences of genetically influenced abnormal development, rather than independent aetiological factors. Few new cases had possible medical aetiologies, refuting claims that recognized disorders are common aetiological influences.  
  Call Number Serial 1112  
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Author (up) Czerlinski, G.; Ypma, T. file  url
doi  openurl
  Title Mechanisms of telomerase-dimer catalysis Type Journal Article
  Year 2008 Publication Journal of Theoretical Biology Abbreviated Journal J Theor Biol  
  Volume 250 Issue 3 Pages 512-523  
  Keywords Allosteric Regulation/physiology; Catalysis; HIV/genetics; Humans; *Models, Genetic; RNA/metabolism/*physiology; Telomerase/metabolism/*physiology; Telomere/metabolism; Templates, Genetic  
  Abstract There is evidence that human telomerase acts as a dimer [Wenz, C., Enenkel, B., Amacker, M., Kelleher, C., Damm, K., Lingner, J., 2001. Human telomerase contains two cooperating telomerase RNA molecules. EMBO J. 20, 3526-3534]. Three possible mechanisms have been proposed. We translate those proposals into three detailed mechanistic models for telomerase action, also introducing optional isomerizations with equilibrium constants inversely related to the number of bound nucleotides. To distinguish between these models by in situ experiments we propose a microscopic system which uses two-photon excitation of fluorescence in a volume of about 0.5 microm(3). A variety of detection strategies and experimental designs are considered; we focus on those best suited to observation of a small volume under limitations imposed by diffusion to and from the reacting micro-volume, and consequently restrict ourselves to constant flow. Numerical simulation is used to help identify an optimal experimental design. The detection of mechanistic changes hinges on linking fluorescence reporters to selected reaction components, either directly (chemically) or indirectly (via an indicator reaction). We show that rapid mixing experiments are better than chemical relaxation experiments, as the statistics of single molecule kinetics affects the latter more than the former. However, some fast reaction steps can only be revealed by chemical relaxation coupled with mixing experiments. We explore connections between our methods and studies of HIV and other systems with RNA to DNA transcription.  
  Call Number Serial 129  
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Author (up) Elliott, K.T.; Neidle, E.L. file  url
  Title Acinetobacter baylyi ADP1: transforming the choice of model organism Type Journal Article
  Year 2011 Publication IUBMB Life Abbreviated Journal IUBMB Life  
  Volume 63 Issue 12 Pages 1075-1080  
  Keywords Acinetobacter/*genetics; Conjugation, Genetic/genetics; Gene Amplification/*genetics; Gene Duplication/*genetics; Gene Transfer, Horizontal/genetics; Genetic Engineering/*methods; Metabolic Engineering/*methods; *Models, Genetic; Mutation/genetics; Transformation, Bacterial/genetics; Transformation, Genetic/*genetics  
  Abstract For more than 25 years, Acinetobacter baylyi ADP1 has been used in molecular biology studies that address a broad range of questions. Recently, the rapid accumulation of data from DNA sequencing, gene expression, protein structure, and other high-throughput methodology has increased the ability to tackle complex topics using sophisticated approaches to metabolic and genetic engineering. While the genetic malleability of ADP1 makes it an ideal organism for such investigations, A. baylyi ADP1 has yet to become a common choice for bacterial studies. This review describes examples of ADP1-based studies that exploit its highly efficient system for natural transformation and chromosomal incorporation of exogenous DNA. These studies focus on a wide array of problems, including gene duplication and amplification, horizontal gene transfer, bioreporters, and metabolic reconstruction. Interesting results in these diverse areas highlight the utility of using A. baylyi in laboratory and industrial settings.  
  Call Number Serial 328  
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Author (up) Fearon, E.R.; Vogelstein, B. file  url
  Title A genetic model for colorectal tumorigenesis Type Journal Article
  Year 1990 Publication Cell Abbreviated Journal Cell  
  Volume 61 Issue 5 Pages 759-767  
  Keywords Alleles; Chromosome Deletion; Colorectal Neoplasms/*genetics; Heterozygote; Humans; Models, Genetic; Mutation; Oncogenes/genetics; Suppression, Genetic  
  Call Number Serial 1723  
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Author (up) Hatemi, P.K.; McDermott, R. file  url
  Title The genetics of politics: discovery, challenges, and progress Type Journal Article
  Year 2012 Publication Trends in Genetics : TIG Abbreviated Journal Trends Genet  
  Volume 28 Issue 10 Pages 525-533  
  Keywords Animals; Genetic Markers; Humans; Models, Genetic; Politics; Social Behavior  
  Abstract For the greater part of human history, political behaviors, values, preferences, and institutions have been viewed as socially determined. Discoveries during the 1970s that identified genetic influences on political orientations remained unaddressed. However, over the past decade, an unprecedented amount of scholarship utilizing genetic models to expand the understanding of political traits has emerged. Here, we review the 'genetics of politics', focusing on the topics that have received the most attention: attitudes, ideologies, and pro-social political traits, including voting behavior and participation. The emergence of this research has sparked a broad paradigm shift in the study of political behaviors toward the inclusion of biological influences and recognition of the mutual co-dependence between genes and environment in forming political behaviors.  
  Call Number Serial 520  
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Author (up) Kass, S.U.; Pruss, D.; Wolffe, A.P. file  url
  Title How does DNA methylation repress transcription? Type Journal Article
  Year 1997 Publication Trends in Genetics : TIG Abbreviated Journal Trends Genet  
  Volume 13 Issue 11 Pages 444-449  
  Keywords Animals; Chromatin/chemistry/genetics; *DNA Methylation; Models, Genetic; *Transcription, Genetic  
  Abstract DNA methylation has an essential regulatory function in mammalian development, serving to repress nontranscribed genes stably in differentiated adult somatic cells. Recent data implicate transcriptional repressors specific for methylated DNA and chromatin assembly in this global control of gene activity. The assembly of specialized nucleosomal structures on methylated DNA helps to explain the capacity of methylated DNA segments to silence transcription more effectively than conventional chromatin. Specialized nucleosomes also provide a potential molecular mechanism for the stable propagation of DNA methylation-dependent transcriptional silencing through cell division.  
  Call Number Serial 1547  
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Author (up) Lu, Z.-xiang; Peng, J.; Su, B. file  url
  Title A human-specific mutation leads to the origin of a novel splice form of neuropsin (KLK8), a gene involved in learning and memory Type Journal Article
  Year 2007 Publication Human Mutation Abbreviated Journal Hum Mutat  
  Volume 28 Issue 10 Pages 978-984  
  Keywords Alternative Splicing; Animals; Base Sequence; Cognition; Evolution, Molecular; Genetic Variation; HeLa Cells; Humans; Kallikreins--genetics; Learning; Memory; Models, Genetic; Molecular Sequence Data; Mutation; Sequence Homology, Nucleic Acid  
  Abstract Neuropsin (kallikrein 8, KLK8) is a secreted-type serine protease preferentially expressed in the central nervous system and involved in learning and memory. Its splicing pattern is different in human and mouse, with the longer form (type II) only expressed in human. Sequence analysis suggested a recent origin of type II during primate evolution. Here we demonstrate that the type II form is absent in nonhuman primates, and is thus a human-specific splice form. With the use of an in-vitro splicing assay, we show that a human-specific T to A mutation (c.71-127T>A) triggers the change of splicing pattern, leading to the origin of a novel splice form in the human brain. Using mutation assay, we prove that this mutation is not only necessary but also sufficient for type II expression. Our results demonstrate a molecular mechanism for the creation of novel proteins through alternative splicing in the central nervous system during human evolution.  
  Call Number Serial 40  
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Author (up) Pawlowska, T.E.; Taylor, J.W. file  url
  Title Organization of genetic variation in individuals of arbuscular mycorrhizal fungi Type Journal Article
  Year 2004 Publication Nature Abbreviated Journal Nature  
  Volume 427 Issue 6976 Pages 733-737  
  Keywords Cell Nucleus/*genetics; DNA, Plant/genetics; DNA, Ribosomal/genetics; Evolution, Molecular; Fungi/*cytology/*genetics/physiology; *Genetic Variation; Genome, Fungal; *Models, Genetic; Molecular Sequence Data; Plants/microbiology; Polymorphism, Genetic/genetics; Recombination, Genetic/genetics; Reproduction, Asexual/*genetics; Spores, Fungal/cytology/genetics  
  Abstract Arbuscular mycorrhizal (AM) fungi (Glomeromycota) are thought to be the oldest group of asexual multicellular organisms. They colonize the roots of most land plants, where they facilitate mineral uptake from the soil in exchange for plant-assimilated carbon. Cells of AM fungi contain hundreds of nuclei. Unusual polymorphism of ribosomal DNA observed in individual spores of AM fungi inspired a hypothesis that heterokaryosis--that is, the coexistence of many dissimilar nuclei in cells--occurs throughout the AM fungal life history. Here we report a genetic approach to test the hypothesis of heterokaryosis in AM fungi. Our study of the transmission of polymorphic genetic markers in natural isolates of Glomus etunicatum, coupled with direct amplification of rDNA from microdissected nuclei by polymerase chain reaction, supports the alternative hypothesis of homokaryosis, in which nuclei populating AM fungal individuals are genetically uniform. Intrasporal rDNA polymorphism contained in each nucleus signals a relaxation of concerted evolution, a recombination-driven process that is responsible for homogenizing rDNA repeats. Polyploid organization of glomeromycotan genomes could accommodate intranuclear rDNA polymorphism and buffer these apparently asexual organisms against the effects of accumulating mutations.  
  Call Number Serial 929  
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Author (up) Podlich, D.W.; Cooper, M. file  url
  Title QU-GENE: a simulation platform for quantitative analysis of genetic models Type Journal Article
  Year 1998 Publication Bioinformatics (Oxford, England) Abbreviated Journal Bioinformatics  
  Volume 14 Issue 7 Pages 632-653  
  Keywords Computer Simulation; Epistasis, Genetic; Genotype; Models, Genetic; Software  
  Abstract MOTIVATION: Classical quantitative genetics theory makes a number of simplifying assumptions in order to develop mathematical expressions that describe the mean and variation (genetic and phenotypic) within and among populations, and to predict how these are expected to change under the influence of external forces. These assumptions are often necessary to render the development of many aspects of the theory mathematically tractable. The availability of high-speed computers today provides opportunity for the use of computer simulation methodology to investigate the implications of relaxing many of the assumptions that are commonly made. RESULTS: QU-GENE (QUantitative-GENEtics) was developed as a flexible computer simulation platform for the quantitative analysis of genetic models. Three features of the QU-GENE software that contribute to its flexibility are (i) the core E(N:K) genetic model, where E is the number of types of environment, N is the number of genes, K indicates the level of epistasis and the parentheses indicate that different N:K genetic models can be nested within types of environments, (ii) the use of a two-stage architecture that separates the definition of the genetic model and genotype-environment system from the detail of the individual simulation experiments and (iii) the use of a series of interactive graphical windows that monitor the progress of the simulation experiments. The E(N:K) framework enables the generation of families of genetic models that incorporate the effects of genotype-by-environment (G x E) interactions and epistasis. By the design of appropriate application modules, many different simulation experiments can be conducted for any genotype-environment system. The structure of the QU-GENE simulation software is explained and demonstrated by way of two examples. The first concentrates on some aspects of the influence of G x E interactions on response to selection in plant breeding, and the second considers the influence of multiple-peak epistasis on the evolution of a four-gene epistatic network.  
  Call Number Serial 19  
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Author (up) Prokopuk, L.; Western, P.S.; Stringer, J.M. file  url
  Title Transgenerational epigenetic inheritance: adaptation through the germline epigenome? Type Journal Article
  Year 2015 Publication Epigenomics Abbreviated Journal Epigenomics  
  Volume 7 Issue 5 Pages 829-846  
  Keywords Adaptation, Physiological/genetics; Animals; *Epigenesis, Genetic; Epigenomics/*methods; Evolution, Molecular; Germ Cells/*metabolism; Humans; Inheritance Patterns/*genetics; Mice; Models, Genetic; epigenetic inheritance; epigenetics; evolution; germline; transgenerational epigenetic inheritance  
  Abstract Epigenetic modifications direct the way DNA is packaged into the nucleus, making genes more or less accessible to transcriptional machinery and influencing genomic stability. Environmental factors have the potential to alter the epigenome, allowing genes that are silenced to be activated and vice versa. This ultimately influences disease susceptibility and health in an individual. Furthermore, altered chromatin states can be transmitted to subsequent generations, thus epigenetic modifications may provide evolutionary mechanisms that impact on adaptation to changed environments. However, the mechanisms involved in establishing and maintaining these epigenetic modifications during development remain unclear. This review discusses current evidence for transgenerational epigenetic inheritance, confounding issues associated with its study, and the biological relevance of altered epigenetic states for subsequent generations.  
  Call Number Serial 2001  
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