some inconvenient truths about sex chromosome dosage
... mechanisms to balance gene dose are extraordinarily complex, and the requirement of a similar and independent mechanism for all sex chromosome systems presents a substantial evolutionary barrier to sex chromosome evolution. Yet we know that nonhomologous sex chromosomes occur in countless lineages, ...
... mechanisms to balance gene dose are extraordinarily complex, and the requirement of a similar and independent mechanism for all sex chromosome systems presents a substantial evolutionary barrier to sex chromosome evolution. Yet we know that nonhomologous sex chromosomes occur in countless lineages, ...
Multilocus genetic models of handedness closely resemble
... variance in fitness is contributed by mutations of large effect that are very rare in the population”30 (p. 1755), a conclusion similarly made by others.31 It is not surprising that GWASs have problems, and equally unsurprising that handedness has similar problems. Implications for genetic models of ...
... variance in fitness is contributed by mutations of large effect that are very rare in the population”30 (p. 1755), a conclusion similarly made by others.31 It is not surprising that GWASs have problems, and equally unsurprising that handedness has similar problems. Implications for genetic models of ...
Bottleneck Effect on Genetic Variance: A Theoretical
... Throughout this article, symbols with subscripts 0 and F always refer to populations before and after the bottleneck event, respectively; symbols without subscripts 0 and F may refer to both. Mutation parameters: Information on rates, effects, and dominance coefficients of polygenic mutations is ava ...
... Throughout this article, symbols with subscripts 0 and F always refer to populations before and after the bottleneck event, respectively; symbols without subscripts 0 and F may refer to both. Mutation parameters: Information on rates, effects, and dominance coefficients of polygenic mutations is ava ...
Allelic Variation at the Rht8 Locus in a 19th
... Copyright © 2012 Linnéa Asplund et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Wheat breeding during the 20th century has pu ...
... Copyright © 2012 Linnéa Asplund et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Wheat breeding during the 20th century has pu ...
Levels of inbreeding depression over seven generations of selfing in
... low outcrossing rates and reduced male longevity (Weeks et al., 2001a,b), as long as inbreeding depression is not substantially ‘purged’ from populations after continued inbreeding, as could occur if inbreeding depression were caused by many recessive deleterious alleles scattered throughout the gen ...
... low outcrossing rates and reduced male longevity (Weeks et al., 2001a,b), as long as inbreeding depression is not substantially ‘purged’ from populations after continued inbreeding, as could occur if inbreeding depression were caused by many recessive deleterious alleles scattered throughout the gen ...
The Ecology and Evolutionary Dynamics of Meiotic Drive
... Meiotic drive occurs when alleles, haplotypes, or chromosomes subvert mechanisms of fair segregation to obtain greater than Mendelian transmission at the expense of homologues. Sandler and Novitski [1] first used the term ‘meiotic drive’ to describe biased transmission that results as ‘a consequence ...
... Meiotic drive occurs when alleles, haplotypes, or chromosomes subvert mechanisms of fair segregation to obtain greater than Mendelian transmission at the expense of homologues. Sandler and Novitski [1] first used the term ‘meiotic drive’ to describe biased transmission that results as ‘a consequence ...
An Analytically Tractable Model for Competitive Speciation
... ecological trait. The mating activity factors M(X) are chosen such that all phenotypes contribute to the offspring pool according to their frequency in the mating population. This is achieved by setting f(X) p 1 for all X and solving the resultant linear equation system (see app. A). Model 2: sexual ...
... ecological trait. The mating activity factors M(X) are chosen such that all phenotypes contribute to the offspring pool according to their frequency in the mating population. This is achieved by setting f(X) p 1 for all X and solving the resultant linear equation system (see app. A). Model 2: sexual ...
Emergent Neutrality in Adaptive Asexual Evolution
... mutations. We show that these interactions partition the adaptive dynamics into strongly beneficial driver mutations, which fix without substantial interference, and beneficial or deleterious passenger mutations, which suffer strong positive or negative interference. Our analytical approach differs fro ...
... mutations. We show that these interactions partition the adaptive dynamics into strongly beneficial driver mutations, which fix without substantial interference, and beneficial or deleterious passenger mutations, which suffer strong positive or negative interference. Our analytical approach differs fro ...
Evolution 2010 Wilkins
... unproblematic, and most likely indistinguishable from the evolutionary end point that would be reached by an unimprinted locus, because the phenotypes that maximize patrilineal and matrilineal fitness are likely to be quite similar in most cases. However, if we consider a pair of antagonistic loci ( ...
... unproblematic, and most likely indistinguishable from the evolutionary end point that would be reached by an unimprinted locus, because the phenotypes that maximize patrilineal and matrilineal fitness are likely to be quite similar in most cases. However, if we consider a pair of antagonistic loci ( ...
Bisexual branching processes to model extinction conditions for Y
... contrary, if the number of females is less than or equal to the number of males, all the females mate and must choose the genotype of their mates. However, since all the males have the same phenotype, each of the Fn+1 females makes a blind choice between the MRn+1 males with R genotype and the Mrn+ ...
... contrary, if the number of females is less than or equal to the number of males, all the females mate and must choose the genotype of their mates. However, since all the males have the same phenotype, each of the Fn+1 females makes a blind choice between the MRn+1 males with R genotype and the Mrn+ ...
Stanford Encyclopedia of Philosophy
... is also only 2.0 units high. Total genetic variance, V G , is actually the sum of all the genetic variance. In the simplified case presented here this is (4) V G = V A + V D The implied equation for V P from the discussion so far is (1′) V P = V A + V D + V E But this equation still oversimplifies t ...
... is also only 2.0 units high. Total genetic variance, V G , is actually the sum of all the genetic variance. In the simplified case presented here this is (4) V G = V A + V D The implied equation for V P from the discussion so far is (1′) V P = V A + V D + V E But this equation still oversimplifies t ...
Waddington`s Legacy in Development and
... mental pathways to produce standard pheWaddington's early interests in theoreti- notypes despite environmental or genetic cal biology, fostered in the Theoretical Biol- influences that would otherwise disrupt ogy Club, were manifested in his editorship development. It is the buffering of develof a f ...
... mental pathways to produce standard pheWaddington's early interests in theoreti- notypes despite environmental or genetic cal biology, fostered in the Theoretical Biol- influences that would otherwise disrupt ogy Club, were manifested in his editorship development. It is the buffering of develof a f ...
Pleiotropic effects of methoprene-tolerant (Met), a gene involved in
... fecundity attributed to alleles of Met was negative, indicating consistent pleiotropic effects among alleles on these traits. The allelic effects of Met support genetic models where pleiotropy at genes associated with hormone regulation can contribute to the evolution of life history traits. ...
... fecundity attributed to alleles of Met was negative, indicating consistent pleiotropic effects among alleles on these traits. The allelic effects of Met support genetic models where pleiotropy at genes associated with hormone regulation can contribute to the evolution of life history traits. ...
Azza Ahmed Ibrahim Abo senna_GST paper
... leukemia has revealed a great number of non-random chromosome abnormalities. In many instances, molecular studies of these abnormalities identified specific genes implicated in the process of leukemogenesis (Mrozek et al., 2004) The environmental causes of acute leukemia, which have increased in the ...
... leukemia has revealed a great number of non-random chromosome abnormalities. In many instances, molecular studies of these abnormalities identified specific genes implicated in the process of leukemogenesis (Mrozek et al., 2004) The environmental causes of acute leukemia, which have increased in the ...
A Unified Approach to the Evolutionary Consequences of Genetic
... combination of genetic and nongenetic mechanisms. Following definitions introduced previously (Bonduriansky and Day 2009), nongenetic mechanisms are mediated by the transmission to offspring of an element of the parental phenotype or environment. The transmissible factor mediating nongenetic inherit ...
... combination of genetic and nongenetic mechanisms. Following definitions introduced previously (Bonduriansky and Day 2009), nongenetic mechanisms are mediated by the transmission to offspring of an element of the parental phenotype or environment. The transmissible factor mediating nongenetic inherit ...
Gene conversion and purifying selection shape nucleotide variation
... spectral sensitivities [16-18]. Even among individuals with normal color vision, the allele frequency of the L opsin gene with Ala at the site 180 instead of Ser is reported to be 30-38% in non-African populations [16-18]. Compared to humans, the incidence of color vision variation is reported to be ...
... spectral sensitivities [16-18]. Even among individuals with normal color vision, the allele frequency of the L opsin gene with Ala at the site 180 instead of Ser is reported to be 30-38% in non-African populations [16-18]. Compared to humans, the incidence of color vision variation is reported to be ...
Genetic Programming: Introduction, Applications, Theory and Open
... For example, given the set of functions f ¼ fþ; $g and the set of terminals t ¼ fx; 1g, a legal GP individual is represented in > Fig. 1. This tree can also be represented by the LISP-like S-expression ðþ x ð$ x 1ÞÞ (for a definition of LISP S-expressions see, for instance, Koza (1992)). It is good ...
... For example, given the set of functions f ¼ fþ; $g and the set of terminals t ¼ fx; 1g, a legal GP individual is represented in > Fig. 1. This tree can also be represented by the LISP-like S-expression ðþ x ð$ x 1ÞÞ (for a definition of LISP S-expressions see, for instance, Koza (1992)). It is good ...
NEW EVIDENCE FOR THE HOMOLOGY OF THE SHORT
... D. melanogaster, the mutation described here undoubtedly is a homologue of the phenotypically similar microchromosomal mutation Cell. The other X chromosomal mutations #960 (10-7. 1958) and #969 (10-9, 1958) were found in the progeny of X-rayed males of a wild strain from the population at Princeton ...
... D. melanogaster, the mutation described here undoubtedly is a homologue of the phenotypically similar microchromosomal mutation Cell. The other X chromosomal mutations #960 (10-7. 1958) and #969 (10-9, 1958) were found in the progeny of X-rayed males of a wild strain from the population at Princeton ...
Reprint
... combination of genetic and nongenetic mechanisms. Following definitions introduced previously (Bonduriansky and Day 2009), nongenetic mechanisms are mediated by the transmission to offspring of an element of the parental phenotype or environment. The transmissible factor mediating nongenetic inherit ...
... combination of genetic and nongenetic mechanisms. Following definitions introduced previously (Bonduriansky and Day 2009), nongenetic mechanisms are mediated by the transmission to offspring of an element of the parental phenotype or environment. The transmissible factor mediating nongenetic inherit ...
The population genetics of mutations: good, bad and indifferent
... There is an enormous range of mutational effects on fitness, and wide differences exist in the strength of other evolutionary forces that operate on populations. This generates an array of complex phenomena that continues to challenge our capacity to mechanistically understand evolution. To make pro ...
... There is an enormous range of mutational effects on fitness, and wide differences exist in the strength of other evolutionary forces that operate on populations. This generates an array of complex phenomena that continues to challenge our capacity to mechanistically understand evolution. To make pro ...
Towards a genodynamics of hybrid zones
... changes would have hastened contact or intensified any existing interactions. It is my subjective impression (based on over 70 field trips) that breeding choruses at undisturbed sites may, in fact. be smaller than those associated with roadside ditches. It seems quite probable that human activities ...
... changes would have hastened contact or intensified any existing interactions. It is my subjective impression (based on over 70 field trips) that breeding choruses at undisturbed sites may, in fact. be smaller than those associated with roadside ditches. It seems quite probable that human activities ...
Evolution of mating types driven by purifying selection
... rely on the prior existence of mating types or sexes and merely reflects the fact that the gamete controlling the cytoplasmic inheritance eliminates its partner’s mtDNA, but not its own (Fig. 1b). Alternatively, a cell can start producing a new nuclear-coded and universally recognized mitochondrial ...
... rely on the prior existence of mating types or sexes and merely reflects the fact that the gamete controlling the cytoplasmic inheritance eliminates its partner’s mtDNA, but not its own (Fig. 1b). Alternatively, a cell can start producing a new nuclear-coded and universally recognized mitochondrial ...
Mende an the Gee 11I+t
... area, Mendel and the other children received agricultural training in school along with their basic education. As an adolescent, Mendel overcame financial hardship and illness to excel in high school and, later, at the Olmutz Philosophical Institute. In 1843, at the age of21, Mendel entered an Augu ...
... area, Mendel and the other children received agricultural training in school along with their basic education. As an adolescent, Mendel overcame financial hardship and illness to excel in high school and, later, at the Olmutz Philosophical Institute. In 1843, at the age of21, Mendel entered an Augu ...
Speciation and patterns of biodiversity
... How many species are there? Diversity is measured by counting species. This is not a straightforward process for several reasons, and the complexities should be kept in mind when analysing patterns of diversity. Counting species is relatively easy when there is a tight association between species id ...
... How many species are there? Diversity is measured by counting species. This is not a straightforward process for several reasons, and the complexities should be kept in mind when analysing patterns of diversity. Counting species is relatively easy when there is a tight association between species id ...
Chromosome Aberrations
... segregation, which can result in abnormal chromosome numbers and abnormal chromosome morphology • The normal ‘complete set’ number of chromosomes in any individual of a species is the euploid number • If that number is not accurate for a given cell, it is considered an aneuploidy • Aneuploid cells a ...
... segregation, which can result in abnormal chromosome numbers and abnormal chromosome morphology • The normal ‘complete set’ number of chromosomes in any individual of a species is the euploid number • If that number is not accurate for a given cell, it is considered an aneuploidy • Aneuploid cells a ...
Polymorphism (biology)
Polymorphism in biology is said to occur when two or more clearly different phenotypes exist in the same population of a species—in other words, the occurrence of more than one form or morph. In order to be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating).Polymorphism as described here involves morphs of the phenotype. The term is also used somewhat differently by molecular biologists to describe certain point mutations in the genotype, such as SNPs (see also RFLPs). This usage is not discussed in this article.Polymorphism is common in nature; it is related to biodiversity, genetic variation and adaptation; it usually functions to retain variety of form in a population living in a varied environment. The most common example is sexual dimorphism, which occurs in many organisms. Other examples are mimetic forms of butterflies (see mimicry), and human hemoglobin and blood types.According to the theory of evolution, polymorphism results from evolutionary processes, as does any aspect of a species. It is heritable and is modified by natural selection. In polyphenism, an individual's genetic make-up allows for different morphs, and the switch mechanism that determines which morph is shown is environmental. In genetic polymorphism, the genetic make-up determines the morph. Ants exhibit both types in a single population.Polymorphism also refers to the occurrence of structurally and functionally more than two different types of individuals, called zooids within the same organism. It is a characteristic feature of Cnidarians.For example, in Obelia there are feeding individuals, the gastrozooids; the individuals capable of asexual reproduction only, the gonozooids, blastostyles and free-living or sexually reproducing individuals, the medusae.