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In short; Theoretically yes. In practicallity no. I agree with this opinion. But, there are some methods to do so. Ligating both ends with specific tags to amplify DNA fragments with the tag specific primer set. If you have different length of DNA fragments in original sample, PCR products could be biased.


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In short; Theoretically yes. In practicallity no. Non-specific PCR require random primers to anneal to a target sequence to initiate replication during PCR. Theoretically this should anneal to every combination of bases and therefore allow the amplification of all DNA (or at least in a fragmented form). Practically, all the primer combinations will have ...


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Certainly in the case of flowering plants a triploid can be created by crossing a diploid by a tetraploid. In this case the teraploid parent will contribute twice as much DNA to the offspring than the diploid parent. Seedless fruits such as bananas, grapes, and watermelons are produced using such crosses. There is also the possibility (and it does occur) ...


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That is an evidence that all the creatures share a same ancestor from evolution. About the origin of the genetic code, scientists proposed some hypotheses to explain it. Chemical principles: From the experiments, scientists found that some amino acid have a selective affinity to certain triplet codons. Biosynthetic expansion: The original creatures may ...


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@yingw response was right, but I will try to explain it a bit better. Say that you had a gene, let's call it the plumb gene. This presents two alleles: P and p. Those alleles behave in a way that gives three different phenotypes depending on the genotype: PP, Pp and pp all have different phenotypes, for example, yellow, green and blue color. If the P and ...


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Preamble Any answer regarding the origins of our biochemical evolutionary origin will be reasonably speculative given that this is a very hard question to scientifically test and this field is generally understudied to say it is pretty much the most fundamental biochemical question. But there are a few reasons why RNA makes sense as the prime genetic ...


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The genus Rhododendron has been divided into some 900 plus species. Often these species hybridize in nature creating what are called hybrid swarms. Although most Rhododendron species are diploids there exists tetraploid, hexaploid, octaploid, and decaploid Rhododendron species. Contact zones between Rhododendron species containing diploid and tetraploids ...


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While it is true that chromosomes contain double-stranded DNA with a double helical structure, in its simplest definition a gene is a linear, contiguous, piece of that double-stranded helix, that is also transcribed by one of the RNA polymerase transcription complexes in the cell. If by "spiral" you mean that the polymerase would rotate around the DNA axis ...


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I think that the rest of the paragraph that you left out of your quotation helps to clarify. The CHO have 21 chromosomes, while the somatic lung cells have 23. Neither case is exact for Chinese Hamsters, 2n = 22. So they have almost the complement of chromosomes that a diploid Chinese hamster somatic cell would have but they are missing one or have one ...


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Well, though it is possible to have SNPs of more than two alleles, and some exist, due to the low probability of having a basepair change twice in the same base-pair (there are aproximately 3.000 Mb in the human genome) and have it in more than 1% of the population (remember we are talking about single nucleotide polymorphism) to classify as a polymorphism ...


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Probably they are not all the same species, as there are many fruit fly species in the UK and all over the world. It is also probable that you are not creating hybrids, as fruit flies have quite specific mating behaviours that change rapidly sometimes even between strains. Anyway, you are assuming that the eggs come with the fruit, but that's hardly ...


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The amount of recombination events does not have anything to do with homologous recombination repair and meiotic homologous recombination, protein-wise. Homologous recombination repair is a "very safe" repair system, especially compared to the alternative option, Non Homologous End Joining, which is really prone to indels. On the other hand, meiotic ...


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You have made an incorrect assumption-- that all the genes on both chromosomes necessarily remain intact. It's possible that they do, and the the translocation is harmless. But the transition point could be within a gene. This would usually lead to that copy of the gene becoming inactive, which can cause diseases just like any other loss-of-function ...


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Without reading the article, given the context that you have mentioned, I think extreme heterozygousity means that most of the individuals in the population are heterozygous (much higher than 50%). So there might be some kind of selection pressure that gives heterozygous individuals a reproductive benefit.


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In the Down syndrom typically, the translocation does not induce (usually; see later) any disease. We call someone carrying the translocation a "balanced carrier". The problem arises after, at the moment of segregation. When balanced carriers reproduce Consider someone who has a translocation as you showed. You showed only one chromosome of each types ...


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Those are the break points of the inversion. So chromosome 4 was cut at p13 and q22 and the fragment was reinserted in the reverse direction, giving a pericentric inversion.


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From the way I have read what you have written z(1-z) translated into a sentence would be the frequency of the neutral variant (z) times the frequency of all other possible variants (1 - z) at the particular time t. Nucleotide diversity is then the average of 2 times the sum of all of the frequencies of neutral variants (z) times the the frequency of all ...


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The term allelic class is defined in Innan and Tajima (1997) Suppose that there are two nucleotides, say A and T, in a particular site.Then, we can divideDNA sequences into two classes: one class includes sequences with A and the other includes sequences with T in this site. We call such a class an allelic class Two elements that were misleading (for ...


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No they are not. High gene density is correlated with GC content. Most genes are found in GC rich isochores, which are not distributed uniformly (as can be seen on any karyotype). It is also shown through direct sequence analysis (gene density shown in red, GC content in green): Venter et al. go on to say: This inhomogeneity, the net result of ...


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C765 is a transgenic Drosophila strain that has a specific Gal4 expression pattern ("embryonic salivary glands and larval wing and leg discs"). Gal4 is a transcription factor from yeast which binds an upstream activating sequence (UAS) and also happens to function in other species (like flies). In the Gal4/UAS system, a strain expressing Gal4, under the ...


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Remi.b talked at great length in his answer about copy-number variation and the generation of new genes. However, I don't think he quite answered what I think is a pretty basic question: How many copies of any particular gene are there in (a human) genome? The answer to that question is also simple: two - one on the chromosome from the mother, and one ...


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The first DNA circle is double-stranded. If you could melt the double-helix completely you would not be able to pull the two stands apart without breaking the sugar-phosphate backbone of at least one of the two strands. This is a topological problem, the two strands are linked to each other. Now consider DNA replication. In the simplest example there is a ...


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Cell cycle Talking about physical copies of gene, we would indeed have at least 1 copy during the haploid phase, 2 copies during the diploid phase and 4 copies during the mitosis (and during the first phase of the meiosis). Of course, species having mitosis during the haploid phase would have 2 copies of the gene during the mitosis. I am not talking about ...


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Yes, people can definitely grow taller than their parents. Height is a polygenic quantitative trait (so affected by many genes), that is also strongly affected by environmental factors. You are also forgetting that there is a sex difference in height (~14 cm, Wright & Cheetham, 1999), so the height of the mother does for instance not set an absolute cap ...


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The short answer is yes, other animals can experience dwarfism, including dogs, although it may not be what you are expecting. Dogs are apparently particularly susceptible but they often are a special case. We've so heavily bred dogs for whatever traits we desire, so now entire breeds are affected by dwarfism, such as dachshunds and corgis. The reality is ...


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They aren't, anymore. It was a fair guess at the time, but first I think we should define what cloning in this context mean. Our own cloning tag says: The process in nature or in the lab by which a new organism is created that is genetically identical to its predecessor. For animals - I'm going to use Dolly as an example since you do as well - when ...


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It's been possible for a long time now. Take a look at this article related to trials with retroviral vectors used for gene therapy trials. A single child developed leukemia, and following that trials across the world were suspended. The article although notes that many countries decided to proceed with trials, since as they say "for the greater good". But ...


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Typically, the ancestral allele is inferred from the allele chimpanzees as our closest relative (and possibly some primates) have. While for most sites humans and chimps have the same allele, there are many cases where the ancestral allele is even completely absent from humans, and where all humans have a different allele from chimpanzees, which we call a ...



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