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First of all: We are not very different on the genetic level - the identity is somewhere around 99.6 to 99.9%. See here for details. If this wouldn't be like this, things like blood transfusions or organ transplants wouldn't work. To identify genes there are different routes. "In the old days" (meaning before the possibility of massive high throughput ...


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Non-homologous end joining indeed induces errors in the affected sequence. But you have to keep in mind, that NHEJ is an emergency repair mechanism which involves a "repair or die" chance. If the chromosomal break is not repaired it is not unlikely that the cell will get into apoptosis, or, even worse, develops into a cancer cell. Introducing small errors is ...


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During Endochondral ossification chondrocytes in the plate are rapidly dividing, newer daughter cells stack facing the epiphysis while the older cells are pushed towards the diaphysis. As the older chondrocytes degenerate, osteoblasts ossify the remains to form new bone. In puberty increasing levels of estrogen, in both females and males, leads to ...


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The DNA polymerase also needs a RNA primer on the leading strand to be able to start polymerization. Afterwards this is not needed anymore, since the replication goes on without a break. On the lagging strand polymerization replication can only work between the replication fork and the next region of double-stranded DNA. See the figure (from here): The ...


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There is no reason for why a certain codon came to represent a certain amino acid. But some reason is attributed to similarity of degenerate codons. Usually the degenerate codons only differ in their last (third) nucleotide. The corresponding first anticodon in tRNA usually bears a modified nucleotide such as inosine which can (promiscuously) pair with A, C ...


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This can be done offline and wont require too much of computational resource. What you will need: A fast short read aligner such as STAR or even bowtie (STAR is faster) Genome sequence (you will have to build index for the genome for your aligner) A GTF annotations file (get it from GENCODE or any other standard genome repository for your organism of ...


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NHEJ is indeed error prone. It is called "non-homologous" because it does not use a "homologous" template from another sequence-matching piece of DNA to guide the repair. Homologous repairs avoid causing mutations because the similar string of DNA acts as a template so that the cell knows what letters to put into the gap. When there's no template, there's ...


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DNA polymerase must catalyse the addition of 4 different nucleotides to the growing strand. This means that it cannot directly determine which base to incorporate at a specific point (how would it 'know' which base to incorporate and how it would it change its specificity for different bases). This means that the specificity for which base pair to ...


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High-fidelity DNA polymerases have several safeguards to protect against both making and propagating mistakes while copying DNA. Such enzymes have a significant binding preference for the correct versus the incorrect nucleoside triphosphate during polymerization. If an incorrect nucleotide does bind in the polymerase active site, incorporation is slowed ...


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Wobble pairing is just a phenomenon and not a hard and fast rule. There are some justifications for why it should exist and that is why it is still called a hypothesis. And this statement is not true:"the base on the third position of the codon and that on the anticodon need not be complementary". The anticodon residue corresponding to the third residue of ...


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The central dogma of molecular biology states that DNA encodes the information for building proteins, the information is copied to messenger RNA through transcription, and messenger RNA is used to build proteins through translation. DNA is also copied through replication. So while it's true that DNA contains the information needed to build a living ...


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I hope you might edit your question to give examples of such comparative injuries. I'm trying hard to imagine an example of this phenomenon, but I can't. The human body doesn't have a tripwire, or a lower limit of injury under which it will not respond. Normally the body mounts appropriate defenses against all injuries from the very minor, like a paper cut, ...


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As Chris mentioned in his comment, 'printing' DNA from scratch (i.e. synthesizing a long strand de novo) is expensive and difficult. Unfortunately, the process of GMO creation is not as simple as assembling a beautiful DNA sequence on the computer, printing it, and then inserting it into a cell. Here's a related question about de novo sequencing. Plant ...


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but with machines its easy. It's not that easy...the Turing machine can't interpret the tape without knowing something about what the 1s and 0's mean. A complied C++ program is gibberish if read through a Perl interpreter. DNA isn't as abstract as that, anyway. A DNA molecule interacts with other molecules based on its shape, which the sequence of ...


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Evidence suggests that the correspondence between DNA codons and amino acids (i.e. the genetic code ) is not random. A good place to start with this interesting topic is the Wikipedia article about the genetic code, in particular, about its origin: Many hypotheses on the evolutionary origins of the genetic code have been proposed. Four themes run through ...


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The chromosomes in your picture do have sister chromatids, they are just very close together. A chromosome needs to pass through replication before it can compact into the typical metaphase chromosome shape depicted above. When I prepare metaphase chromosomes, I usually see a mixture of chromosome sets where the chromatids are close together (like above) and ...


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"I imagine that turtle looking up at that food, and sub-consciously wishing to get to it, constantly straining, for it's entire life time. It seems plausible to me that we (advanced life) could have a biological mechanism to "write" needed alterations into either our own DNA or our reproductive DNA over time, triggering the very specific ...



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