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This process helps with the signal to noise ratio. In theory, you could use the fingerprinting techniques to dice up the few billion copies of the DNA and carefully measure them. However, it is far easier to replicate the DNA to increase the number of molecules of DNA available to the process. Remember, fingerprinting for crime investigations doesn't ...


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The "Central Dogma" is an obsolete concept. It has no biological significance today. It's been outdated for decades since the discovery of reverse transcriptase, but it was never intended to be taken particularly seriously anyway; Crick deliberately gave it its portentous name as a provocative approach, to drive people to think more about the topic and look ...


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Crick’s Central Dogma was actually: The Central Dogma This states that once ‘information’ has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. ...


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It's interesting that not only the leader 19, but also 16 and 17 follow a similar trend. Perhaps their size could be the best weight/length proportion to ensure a safe replication? Then what would have to be explained would be 18, so far to the left. That could be if 18 is newer, resulting from the split of a larger chromosome or the fusion of two smaller, ...


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This Nature paper from 2004, by Jane Grimwood et al. goes at least a long way towards giving an answer to the question of the OP. In short: there were inordinately many duplications, especially during an event 30-40 million years ago, as well as during a much more recent event. These duplications are, uncharacteristically, predominantly intra-chromosomal ...


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There are mechanisms through which the X-chromosome that has been turned into a Barr-body can be re-activated. This happens during cloning, but is also seen in some cells that turn into cancer cells. This paper discusses a lot of intriguing lessons we've learned from transplanting nuclei from one cell to another in frogs and mice. Interestingly, though the ...


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Heteroduplex called patch does not have double-stranded recombinant regions, there is a new fragment in a single strand only. It means that the two strands are not complementary at that regions and as soon as DNA repair systems detects it, the mistake will be corrected. In case of heteroduplex called splice, there are double-stranded changes, which do not go ...


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It is correct that O- and B+ parents cannot produce biological children with A+ and AB+ blood groups, with the exception of a few rare edge cases. Firstly, as noted in the other answer, your grandmother may have the Bombay phenotype. However, this is unlikely, due to the fact that she has been previously hospitalised and it was not noted. Another ...


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Assuming true paternity and correct ABO blood type detection, your grandma could likely have a Bombay phenotype (h/h blood group), which would make her blood look like the O type: http://www.ncbi.nlm.nih.gov/books/NBK2268/ This means that she would be double recessive to (and therefore lack) the H antigen, which is a precursor to A and B antigens. She would ...


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Imagine that mom's chromosome is blue, and dad's is red. If crossing over was happening hundreds of times per chromosome, sure, you could make chromosomes to pass into gametes which were very a very highly shuffled combination of paternal and maternal alleles. It would be blue, red, blue red, blue, red, all up and down the chromosome. But it doesn't. It ...


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You are right but the list is certainly not exhaustive. Here are a few more concepts you may want to consider. Exception of law of dominance: epistasis Allelic effect at a given locus depend on the variants at other loci environment dependence and specific case of frequency dependence The concept of dominance can be used for any quantitative trait. ...


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One is a recurrence equation and the other is a general solution. These are basic concepts of mathematical modelling. Reccurence equation A recurrent equation describes the state of a system (here, heterozygosity $H$) at the next time step given the state in the previous time step. The recurrence relation is $H' = (1-1/2N)\times H$. Given the state $H$, ...


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Definitely not. There is a ton of variation from gene to gene, otherwise, as you say, regulation wouldn't work. That said, the word "promoter" sometimes gets used in different ways. Especially in eukaryotic systems, people will sometimes say "promoter" to mean the entire region upstream of the gene where transcription factors can bind (for yeast, typically ...


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This is not my area, but as nobody has answered yet I'll start the ball rolling to try to encourage a more authoratative response. Long, long ago, before the internet, when I was a post-doc and the emphasis was on bacterial rather than eukaryotic gene expression, I remember hearing something about specific sigma factors differentially controlling initiation ...


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A large part of the body of your question seems relatively unrelated to the main question which is a little confusing. I will focus on the question Is it possible for there to be a random un-mutation of genes? Yes, these are usually called reversed mutation. It is quite common though that a second mutation at a distinct locus may reverse the phenotypic ...


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It requires two genetic constructs to create a conditional KO organism. One parent with a transgene that expresses a DNA recombinase (such as Cre) after the promoter of a gene that is ONLY expressed in your tissue of interest. The other parent contains a modified gene of interest to be removed in the presence of said DNA recombinase but is fully functional ...


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What you've circled is not a heteroduplex. A better name for it would be "crossover" or "junction". Instead, the two duplexes at the bottom of your diagram are what should be labeled heteroduplexes. Your diagram shows one process by which you could generate heteroduplexes starting from homoduplexes. Here's a better picture from the NCI Dictionary of ...


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Before I actually answer your question, let us clear up some problems in your assumptions. The fact that you expect 50% similarity in siblings is a full of several assumptions. Imagine a case of a simple diploid organism with 2 traits. To restate your assumption, if both the parents are heterozygous in either of the two traits, and the alleles present in ...


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I agree with Vance, we need a little more detail to better answer your question. From what I can tell, you are asking whether a single nucleotide polymorphism (SNP) that results in the addition of a cytosine base to your sequence is of concern when examining the methylation signature of that sequence. I would first determine whether the polymorphism is ...


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You are correct that brachydactyly is a dominantly inherited disorder and is usually caused by mutations in the BMPR1B gene. However, not everyone who has the mutation, will have clubbed thumbs (the phenotype). This is due to a phenomenon known as penetrance and expressivity. Penetrance essentially is an all-or-none phenomenon whereby certain individuals ...


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Gene editing is not done on a single cell but a bunch of cells. However, it still does not affect all the cells. Gene editing/therapy for the entire organism works in these cases: Stem cells are edited, which give rise to many other somatic cells. Usually done in case of gene therapy in which the stem cells are obtained from the patient, edited and re-...


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A chromosome is simply a length or segment of DNA. Bacteria have few structural proteins on their DNA, and they have one circular chromosome. In humans, before DNA replication, the nucleus contains 46 strands of DNA, i.e. chromosomes (22 chromosomes in two copies and usually two X or one X and one Y for males and females, respectively). All chromosomes are ...


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It can be a little confusing. A genetic allele is just a portion of the genome responsible for an observable trait or phenotype. Examples of phenotypes consist of your example (eye color) and millions of others. As @swbarnes alluded to, most phenotypes are complex phenotypes, meaning they are not described by a single genetic locus. Height, weight, hair ...


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I think the "gene drive" that you are talking about involves the CRISPR system, and it is an engineered run of code that deliberately makes that allele 'super dominant' (by making more CRISPR components that are loaded with the particular gene replacement instructions), like in a scenario where they are trying to replace the faulty gene for Huntington's ...


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does this mean that we can say for certain (given a correct screen) that the child has a 3/4 chance of having the dominant characteristic (expressed) and a 1/4 chance of having the recess characteristic? If you are sure that the phenotype is 100% determined by that allele only, then yes, barring things like new mutations. Biology always has some ...


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The discovery of genetic sex determination, and determination of sex via male gametes (in XY species, female in ZW), occurred over some time in the late 1800's and early 1900's. Advances were made with methods to stain chromosomes and, in 1891, Henking noted that wasps produced sperm with a varying number of chromosomes. However, he was unable to gather ...


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I'm not sure what you mean by "recombination". Peas have 7 chromosomes. Mendel's seven published traits are each on a different chromosome. Mendel's second law states that all genes assort independently. This is wrong, but it is correct for genes located on different chromosomes, which Mendel's were.


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You can try to use some standart data sources, for example: NASA's Gridded Population of the World - LINK Geonames - LINK



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