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(For the direct answer to your question skip to the end!) Genetic linkage can affect the spread of other genes. The degree of linkage, affected by the rate of recombination between the point (nucleotide, gene etc.) directly under selection and the other point. If the rate of recombination between to given points is low then linkage between them is high and ...


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Genetic hitchhiking / genetic draft From wikipedia Genetic hitchhiking, also called genetic draft or the hitchhiking effect, is when an allele changes frequency not because it itself is under natural selection, but because it is near another gene on the same chromosome that is undergoing a selective sweep. The term "selective sweep" is used improperly ...


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A biomarker, or biological marker, generally refers to a measurable indicator of some biological state or condition. - Wikipedia The presence of certain 'things' (sorry for being vague) in a tissue obtained invasively - via biopsy, for example - are considered biomarkers for, say, a cancer. It could be histopathological - a particular abnormality seen ...


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They queried publications dealing with the lncRNA that studied whether it was functional through over-expression or knockdown. Cells do something measurable in their normal state, that can be observed through microscopy, qPCR, microarray, etc. You use the data as a control which to compare experimental results against. For an over-expression study, for ...


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With many non-coding RNAs, the RNA is the functional endpoint. Therefore, ncRNA "expression" simply refers to the production of that functional component. Similarly to with proteins, this involves looking at differential tissue production of that noncoding RNA (i.e. in which tissues the RNA is produced). Gene expression is defined in the Oxford Dictionary ...


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The best reference I could find is a book chapter (available here as a .pdf) from a book on optimizing the expression of membrane proteins that argues for T7. Although they don't appear to reference a source for that specific claim, some of the references close by could be helpful. It seems as though this applies in general, not just to membrane proteins. ...


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DNA is a chemical, and therefore, its interactions are governed by its shape. There is no way to look at a DNA sequence and know all the ramifications that changing a letter will have on its shape. I could tell you that changing the first two or last two letters of an intron are highly likely to destroy a splice site, but you can't make hard and fast ...


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This isn't a question with a really well accepted answer yet, and comes up quite a lot in e.g. studies of population variation in transcription factor motifs. Usually, we approximate the sequence preferences of a DNA-binding protein with a position weight matrix. A weight matrix will given you a score for two sequences, so the simplest means of quantifying ...


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Most (almost all, AFAIK) mRNAs and lncRNAs start with exons for the reasons already mentioned by David. In a typical splicing event, the nucleotide that is 5' to the splice donor site (lets call it pre-donor) and the one that is 3' to the acceptor site (lets call it post acceptor) are joined together and the intronic sequence between them is removed. If ...


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I think the presence of a single terminator is related to the high processivity of T7 RNA polymerase. T7 RNA polymerase will transcribe a circular plasmid repeatedly before dissociating. The T7 terminator after ORF2 ensures that the transcript terminates efficiently. Based on your schematic, these are the potential mRNA transcripts from that construct: ...


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Thank you for a great question. I would like to start by clarifying some terminology. First, nascent RNA refers to an RNA molecule that is currently being transcribed and has not been processed. Processing can include the splicing out of introns or polyadenylation at the 3' end, for example. Mature RNA is (typically) spliced and polyadenylated. Second, ...


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As far as I am aware, transcripts always start and end with exons. The reasons I wouldn’t expect otherwise (apart from my observations when examining Drosophila transcripts) are given below. As you will be aware, the spliceosome (at least for mRNA) is a highly sophisticated multi-component ribonuclear protein complex, and has functions to both splice out ...


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First off, AOZ has a wonderful page about titanium alloy uses in medical applications you should read and that most of my info is coming from: Suitability of Titanium for Implant Purposes I think you're having a couple of easy to correct misconceptions. First, titanium alloys are used for medical implants and replacements because they're lightweight, ...


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Normally only one strand of DNA is transcribed. This is possible because for the RNA polymerase to bind and start transcribing the DNA into mRNA (or pre-mRNA) a special sequences on the DNA called a promoter is needed. Promoters will normally only be positioned to allow transcription in one direction, i.e. of one DNA strand. Bacteria and their viruses ...


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If a piece of DNA were to be transcribed on both strands, at the same time, the transcription complexes would collide and inhibit each other, like steric hindrance. If you could overcome this interference and synthesize primary transcripts from both strands, it follows that the two RNAs would hybridize to each other and form complementary RNA-RNA hybrids. ...


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An exon can have multiple stop codons but the first codon will terminate the ORF. The remainder of the exon will be a part of the 3'UTR. However, there are some cases in which stop codon readthrough happens [1]. In these cases an internal stop codon does not terminate the translation and the ribosome reads through it. During this process an aminoacyl-tRNA ...


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Human female cells contain most of the genetic information required to make a male, but they do not contain a critical component: The Y chromosome. This is a relatively small chromosome. Wikipedia claims we have identified around 200 genes on it to date, compared to estimates of 20,000 - 25,000 genes overall in the human genome. Importantly for your ...


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"To me it seems like both clone based sequencing and shotgun sequencing could have been used together," I believe they were. The public project cut up the genome into BACs and shotgunned every BAC, and then put the BACs together, while Venter used some sequence position information from the public effort to help him place his shotgun pieces. ...


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While overlapping antisense RNAs are quite well known, there are very few examples in which both the RNAs from the pair can code for proteins. However, it is not impossible. I can cite one validated example: RU2S (DCDC2) and RU2AS (KAAG1) pair. While RU2S is constitutively and ubiquitously expressed, RU2AS is specifically expressed in kidney, bladder, ...



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