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Just googling, they are SSLPs. You do PCR, and the different alleles make different length amplicons. Looks like there is some kind of artifact that causes some of the amplicons to have peaks that look 2, or 4, or 6 letters shorter than the true length. So for the top marker, the 211 bp long allele is linked to the disease, and for the other one, the 118 ...


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The traces you have come from Sanger sequencing. N in genetics means nucleotide (surprising right?). N is used when the base at a given location is unknown (or could be any base pairs). In your case you have Ns because the base-calling software is unable to determine the nucleotide. The first N is due to two peaks overlapping (G and A signals) and the ...


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So the two Ns that you see are not necessarily variants, but rather likely just poor quality reads. Essentially when you sequence DNA and the sequencer can't make a call as to what the base is, it will just designate it N meaning that the base could be any of the four DNA bases. As for finding the reading from, if you know this sequence contains a stop ...


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Summary: In bacteria or organisms with only one well defined replication origin and a circular chromosome, yes for a given DNA region the same strand is replicated discontinuously. In high order animals, which replicate chromosomes using several origins of replication (ori), this is less clear as the way ori are recognized is still not fully understood but ...


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DNA polymerase act on same strand discontinuously. Because polymerization always occurs 5'->3' and it does not change between the replication cycles. Mutations are more common in the discontinuous replication, as DNA ligase adds more nucleotides between the okazaki fragments and hence they have highest probability of attaining mutation.


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Short answer is that higher temperature favors annealing of longer sequences. There are number of ways to calculate melting temperature, but all of them produce similar results: longer polymers require more thermal energy to melt. Hence, quick cooling from higher (say, from 95C thermocycler can cool in 10-12 sec) to RT/4C will favor re-annealing of circular ...


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mtDNA is present in a much higher copy number per cell than nuclear DNA. According to this paper, there are approximately 4000 or so mitochondrial DNA copies per human muscle cell. copy number of mtDNA per diploid nuclear genome in myocardium was 6970 ± 920, significantly higher than that in skeletal muscle, 3650 ± 620 (P = 0.006). This makes it far ...


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If you're looking for a strictly and directly DNA-DNA mediated effect (no histones, no transcription involved) I'd look for sequence effects on chromatin remodelling, modulating access of transcription factors (TFs) to their elements. Something about this might be in this paper: Szerlong, H. J., & Hansen, J. C. (2011). Nucleosome distribution and linker ...


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Since DNA is an acid it is reasonable to ask: what is the pKa of the phosphate residues located all along the polynucleotide's sugar-phosphate backbone? Apparently that number is at a pH between 1 and 2 (http://www.bio.brandeis.edu/classes/biochem104/DNA_lecture.pdf). That means at physiological pH ranges (for example, the pH found inside the nucleus or ...


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DNA stands for deoxyribonucleic acid. Acid, by definition and mechanism in aqueous environment, is something that donates proton ($H^+$). HCl dissolved in water will donate proton to solution, thus bringing pH down, since $pH=-log_{10}[H^+]$. DNA, being an acid, donates protons to water and brings pH down a notch. Just like in case with HCl, it has nothing ...


0

So cryopreservation would be the long-term mode of storage, and you'd do something like store your sample in a cryonic freezer supplied w/ liquid nitrogen at -196C. Cellgro provides some recommendations for cryopreservation here. Keep in mind, cryonic freezers are typically pricey, but broady, the idea is you need to keep your cells at the right temperature, ...


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This "undifferentiation" is actually possible and it is known as induced pluripotent stem cell (iPSC). The first "undifferentiation" cells i.e. iPSCs were mouse fibroblasts created in 2006 by researchers in Shina Yamanaka's lab who got the Nobel prize in 2012 for this work. You can find further reading on this topic on the according Wikipedia-Page or more ...


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Might I suggest you go directly to the source? Here is a link to a paper published by Francis Crick (et al) in 1957 entitled: 'Codes Without Commas' http://www.ncbi.nlm.nih.gov/pmc/articles/PMC528468/


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I think the picture will help you. In fact, to determine which kind of rearrangement for the chromosomal, we need to define an "orientation". However, this orientation is not fixed. It is a definition compared with the two chromosomes before and after the rearrangement. As the picture shows, the duplicated sequence after rearrangement should be in the same ...


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First off this is called genetic mosaicism and indeed mitotic recombination is a contribution factor. Mitotic crossover events involve the exchange, by homologous recombination, of regions of chromosomes. 60% of homologous recombination events might occur during G1 and 40% of those event occurs after chromosomes are replicated (see this paper). For twin ...


2

B-form DNA is wrapped around histones in a left-handed manner resulting in a left-handed solenoidal superhelix (see that, that and this). The reason for this wrapping is that it reduces the helical tension. This post has more information about DNA helical tension. Also note that exceptions exist (i.e. right-ended direction) especially for histone at the ...


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Either the gene is present in multiple copies (especially possible if it is in a plasmid) or multiple RNA polymerases are transcribing it, each beginning from the start site one after the other with some amount of time delay, much like multiple ribosomes translate the same mRNA to increase rate of protein production.


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Multiple RNA Polymerase transcription complexes engaged on the lacZ gene at the same time, staggered along the gene.



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