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| | Population genetics: |
 | | If one or more condition is not met, allele frequencies will change, and evolution will take place. | | | If the five conditions are met, then there is no change in allele frequencies over time, and no evolution takes place | | | Migration of individuals can quickly change allele frequencies in a population |
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http://www.ku.edu/~bio152/outline11.html
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| | Untitled |
| | The Hardy-Weinberg equilibrium (in which no change in allele frequency occurs - i.e. | | | They happen to be the same 5 conditions discussed above, except now we are considering the opposite condition. | | | , the frequency of this genotype in the Hardy-Weinberg equation. |
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http://www.botany.uga.edu/~darley/btny1210/Nov20Fri.htm
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| | Hardy-Weinberg--Selection & Mutation |
| | Adding selection to the H-W analysis: Changes in allele frequencies | | | Empirical Research on Allele Frequency Change by Selection | | | no change in allele frequencies (conclusion 1 holds) |
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http://users.tamuk.edu/kfjab02/Biology/EVOLUTION/b3301_ch005.htm
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| | Allele Frequency |
| | Evolution is only concerned about the change in allele frequency in a population. | | | Instead, the environmental stressor changes allele frequency in some way, thus changing the population. | | | Thanks for taking the time to read my views. |
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http://www.ridgecrest.ca.us/~do_while/sage/v7i9e.htm
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| | Welcome to GoLive CyberStudio 3 |
| | Sometimes, having one particular allele will confer on an individual an increased chance of survival and reproduction. | | | In reality, it is infrequent that these conditions are met. | | | The Hardy-Weinberg principle states that under a set of presumed conditions, genotype frequencies will be constant from one generation to another. |
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http://www.emunix.emich.edu/~rwinning/genetics/populat4.htm
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| | PCB 4673 Computer Lab Assignment 3 |
| | More specifically, this movement is random with respect to the direction in which the allele frequencies change. | | | Second, the true allele frequencies determine the probability of movement in any particular direction. | | | Set the initial frequencies at all six loci at "independently" and set the initial frequency of the "A" allele at locus 1 at a value of your choice. |
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http://www.bio.fsu.edu/courses/pcb4673/computer_lab_assignment3.html
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| | The Hardy-Weinberg Equilibrium |
| | Potentially harmful recessive alleles - invisible in the parents - become exposed to the forces of natural selection in the children. | | | The change in frequency of the dominant allele (Δp) after one generation is expressed by the equation | | | The outcome is a gradual change in the gene frequencies in that population. |
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http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/H/Hardy_Weinberg.html#When_the_Hardy-Weinberg_Law_Fails_to_Apply
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| | MUTATION AND MIGRATION |
| | The change in allele frequency from the migration into the harbor can be defined as above: | | | Depending on the relative strengths of these two opposing forces, an equilibrium condition can arise. | | | This is useful because it lets us calculate a theoretical equilibrium frequency which is defined as the point at which there is no more change in allele frequencies, i.e. |
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http://biomed.brown.edu/Courses/BIO48/7.mutation
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| | Population Genetics |
| | G.H. Hardy and G. Weinberg, both in 1908, made their mark on evolutionary biology by pointing out that genotype frequency could vary in the absence of any change in allelic frequency. | | | Bonus points for a sixth condition which makes such equilibria meaningful: [PEEK] | | | The study of evolution, therefore, at least in part is a study of conditions which lead to deviations from Hardy-Weinberg equilibrium. |
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http://www.mansfield.ohio-state.edu/~sabedon/biol1508.htm
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| | Allele - Wikipedia, the free encyclopedia |
| | A dominant phenotype will be expressed when only one allele of its associated type is present, whereas a recessive phenotype will only be expressed when both alleles are of its associated type. | | | In an organism which has two copies of each of its chromosomes (a diploid organism), two alleles make up the individual's genotype. | | | A wild type allele is an allele which is considered to be "normal" for the organism in question, as opposed to a mutant allele which is usually a relatively new modification. |
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http://en.wikipedia.org/wiki/Allele
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| | Allele frequency - Wikipedia, the free encyclopedia |
| | When these conditions apply, a population is said to be in Hardy-Weinberg equilibrium. | | | Four out of five will be occupied by other variants of the gene, of which there may be one or many. | | | Population genetics studies the different "forces" that might lead to changes in the distribution and frequencies of alleles -- in other words, to evolution. |
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http://en.wikipedia.org/wiki/Allele_frequency
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| | ABO Frequencies |
| | The equation can be extended to multiple alleles and the ABO blood group system with three alleles can be analyzed by H-W. First, the basic allele frequency statement of the H-W equation is modified as follows: | | | The frequency of blood type B individuals is equal to q² + 2qr. | | | The frequency of blood type A individuals is equal to p² + 2pr. |
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http://www.people.virginia.edu/~rjh9u/abofreq.html
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| | Natural Selection and |
| | What happens to the frequencies of genotypes (and alleles) and number of offspring when one of the Hardy-Weinberg assumptions is broken? | | | Understand the Hardy-Weinberg equilibrium model and its assumptions. | | | This potential generation is reduced in numbers because individuals that bear the lethal allele in the homozygous recessive condition are eliminated from the population by natural selection. |
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http://www.usd.edu/biol/labs/151/natsel.htm
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| | Problem Three |
| | An empirical example from a population cage experiment involving fruit flies with a lethal allele that affects eye size and shape in heterozygotes | | | Try using these equations to explore the effects of different genetic mechanisms on response to selection | | | Allele frequency change becomes almost zero per generation |
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http://ib.berkeley.edu/courses/ib162/NatSel2.htm
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| | Random Genetic Drift |
| | We will also learn what happens to the genetic variance when we relax the assumption of random mating. | | | This is an example of using conditional probability: | | | With drift, there is some probability that the allele frequency in the next generation could be any value. |
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http://www.zoology.ubc.ca/~whitlock/bio434/LectureNotes/04.Drift/Drift.html
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| | Zoology 304, Evolution |
| | Question 4.1 concerns the rate of allele-frequency change in relation to dominance. | | | If you would like to explore this model of selection, by experimenting (i.e., playing) with the parameters of selection coefficient, allele frequency, and dominance and then plotting the results, send a request to Dr. King, and the program which created these graphs will be returned as an attachment. | | | For a recessive allele, the initial slow phase would be much, much longer. |
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http://www.science.siu.edu/zoology/king/304/prob04.htm
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| | DownFreq Documentation - Documentation for DOWNFREQ program |
| | 1 = founders; 2 = all individuals; 3 = frequencies given in original indata.dat | | | However, in the LINKAGE programs, there is a bottleneck in terms of how large of a problem can be analyzed, and that bottleneck is related to the number of possible haplotypes the program must consider. | | | However, asymptotically this also will give an unbiased estimate of the allele frequencies, and when you have large sets of small pedigrees with founders often untyped, this method may be more reliable than the former. |
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http://watson.hgen.pitt.edu/docs/Downfreq2-Document.html
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| | Hardy Weinberg Equation |
| | The frequency of carriers (heterozygotes) for the CF allele is | | | The frequency of the normal allele is equal to 1 - the frequency of the Cf allele | | | Recessive traits: If the frequency of a recessive trait (such as CF or PKU) is known, it is possible to calculate allele frequencies and genotype frequencies using the Hardy Weinberg equation and its assumptions as follows: |
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http://wsrv.clas.virginia.edu/~rjh9u/hwequa.html
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| | Bio 101 - Introductory Biology: Population Genetics Homework |
| | Cooley's anemia is caused by a recessive allele "c" when it occurs in the homozygous condition. | | | Calculate the allele frequency for the genotypes of this second generation, and use them to determine the genotype frequencies in the third generation. | | | Assuming a state of H-W equilibrium, what is the frequency of the dominant allele at this locus? |
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http://academic.reed.edu/biology/Courses/BIO101/popgen.html
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| | Allele frequency models |
| | There are two basic models for the allele frequencies. | | | The correlated frequencies model says that they may actually be quite similar. | | | Estimating admixture proportions when most individuals are admixed. |
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http://pritch.bsd.uchicago.edu/software/readme/node19.html
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| | ALLELE FREQUENCY DISTRIBUTION |
| | Among the 205 unrelated individuals 70, 43, 53 and 39 different alleles were detected at D1S7, D7S21, D7S22 and D12S11 loci, with heterozygossity of 92,2%. | | | The characterization of a large number of highly polymorph STR loci along with the construction of well-defined allelic ladders for several of the most easily interpreted loci, allow increased use of these systems in forensic analysis and paternity determination. | | | PCR-based typing of VNTR/STR loci become a technique of growing importance in forensic analysis and paternity testing. |
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http://www.manu.edu.mk/rcgeb/tempus/ALLELEFREQUENCYDISTRIBUTION.html
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| | Random mating and linkage |
| | as departure of gamete frequency from equilibrium expectation. | | | In general, the covariance has a dimension (in this case, frequency squared) and is therefore not comparable across different studies (e.g., the covariance changes if the measurement units change). | | | Allele frequency influences heterozygote frequency; heterozygotes most frequent at intermediate allele frequency. |
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http://www.wsu.edu:8080/~mmorgan/biol519f01/node20.html
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| | Genetics Glossary AB |
| | homozygosity in which the two alleles are alike but unrelated. | | | A mutant strain of microorganism that will proliferate only when the medium is supplemented with some specific substance not required by wild-type organisms. | | | Genetic variance associated with the average effects of substituting one allele for another. |
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http://helios.bto.ed.ac.uk/bto/glossary/ab.htm
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| | Re: did the spartan breeding project leave any measurable effect? |
| | One of the most common genetic disorders of populations of European descent is cystic fibrosis: http://www.ncbi.nlm.nih.gov/htbin-post/Omim/dispmim?219700 The gene is CFTR, described at: http://www.ncbi.nlm.nih.gov/htbin-post/Omim/dispmim?602421 The incidence of the disease in Caucasians is 1/3,300: http://www.urmc.rochester.edu/genetics/CysticFibrosis.htm This gives an allele frequency of about 1.7% for the mutant allele. | | | Population geneticists use a term that is useful to us here called the allele frequency. | | | These people typically do not reproduce, so from the standpoint of allele frequencies, it is exactly like the Spartan situation. |
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http://www.madsci.org/posts/archives/2003-03/1047083696.Ge.r.html
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| | Generating variation: mutation models |
| | Note that only three alleles recognized, but alleles differ by changes at up to six nucleotide sites. | | | allele in generation 1, the allele had to be an | | | (i.e., posit that there is an allele frequency |
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http://www.wsu.edu/~mmorgan/biol519f01/node13.html
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| | Submitted SNP(ss) Report in Submission Format |
| | This particular subset of genotype data was produced by the laboratory CELERA, using individuals from a CEL_caucasian panel. | | | This particular subset of genotype data was produced by the laboratory CELERA, using individuals from a CEL_african_american panel. | | | This particular subset of genotype data was produced by the laboratory CELERA, using individuals from a CEL_asian panel. |
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http://www.ncbi.nlm.nih.gov/SNP/snp_retrieve.cgi?subsnp_id=1345955
(524 words)
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| | ALLELE FREQUENCY CHANGE |
| | In the whole population, natural selection and drift are the main forces leading to allele frequency change. | | | Migration between geographic subpopulations determines genetic structure among subpopulations. |
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http://www.uic.edu/classes/bios/bios101/Alleles/tsld017.htm
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| | ALFRED |
| | in the allele frequency tables to view the genotypes. | | | A resource of gene frequency data on human | | | We have been updating the new ALFRED Map Interface. |
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http://alfred.med.yale.edu/alfred/index.asp
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| | Forensics and Population Genetics |
| | Also, certain alleles are non-existent or have different allele frequencies among various ethnic background in the United States. | | | The smaller pieces of DNA can be identified exactly as particular alleles and prevents the need for “binning” several similar-sized DNA fragments into one pool to which one “allele” frequency is assigned. |
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http://www.mtsu.edu/~rseipelt/web4460a/446forgen.htm
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| | Alfred: A Web-Accessible Allele Frequency Database (ResearchIndex) |
| | The data in ALFRED are modeled based on the experience and needs of a single laboratory, but with the expectation that the database will meet the needs of a much broader scientific community that needs population-specific gene frequency estimates. | | | Online articles have much greater impact More about CiteSeer.IST Add search form to your site Submit documents Feedback | | | Abstract: We present a Web-accessible database (ALFRED) that allows public access to gene frequency data for a diverse set of population samples and genetic systems. |
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http://citeseer.ist.psu.edu/411926.html
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| | ALLELE FREQUENCY CHANGE |
| | Graph of the relationship between gene frequency in one generation and the next. | | | Change in Allele Frequency from one generation to the next |
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http://www.uic.edu/classes/bios/bios101/devolution
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| | Bayes allele frequency software |
| | Calculates estimated allele frequencies based on actual frequencies. |
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http://www.wpic.pitt.edu/WPICCompgen/bayes_allele_frequency_software.htm
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| | ALFRED - Allele Frequency Database - Biotech company |
| | If you are a representative from this organization, you could update/correct the informations on this page with the following form. | | | ALFRED - Allele Frequency Database - Biotech company |
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http://www.lifesciencesworld.com/companies/company-2261.htm
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| | Allele Frequency Distribution Tables |
| | These population data tables show allele frequency distribution in diverse human populations. | | | Ron Fourney, of the Royal Canadian Mounted Police, has provided STRBase with these tables. |
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http://www.cstl.nist.gov/div831/strbase/freq_tab.htm
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| | caspase recruitment domain family, member 4 |
| | Pearson Chi-Square Test ---------------------------------- Chi-Square 2.4007 DF 2 Asymptotic Pr > ChiSq 0.3011 Exact Pr >= ChiSq 0.3269 Effective Sample Size = 166 Frequency Missing = 44 WARNING: 21% of the data are missing. | | | Fisher's Exact Test ---------------------------------- Cell (1,1) Frequency (F) 4 Left-sided Pr Table Probability (P) 0.2633 Two-sided Pr African-American Asthma 11:59 Tuesday, June 18, 2002 77 | | | SNP = 432336 Table of case_cn by gfreq7 case_cn gfreq7 Frequency |
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http://innateimmunity.net/IIPGA2/PGAs/InnateImmunity/CARD4/ADsas
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