rman
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6.
Southern blotting is used to distinguish maternal and paternal copies of chromosome 7 in a single person. The diagram on the top indicates the DNA region that is amplified and the predicted sites of digestion with restriction endonucleases. The site of hybridization of the labeled probe is also indicated. The gel pattern obtained is shown on the bottom. This pattern is most likely indicative of which of the following?
A ) Chromosome walking
B ) Meiotic segregation
C ) Nondisjunction of chromosomes during meiosis
D ) Recombination
E ) Restriction fragment length polymorphism
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| spjokes
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??? E) RFLP
I have to read further
See if this helps Robbins p185 e7
Im as eager as rman to get correct answer
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| sridevibandaru24
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RFLP
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| robin082006
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D?
If endonuclease works, It is expected that 6kb and 4kb are seen in electrophoresis. In this case, 10 kb is seen--> may be 1. recombination or 2. mutation that makes the gene is not digested by endonuclease.
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| rman
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Ok, I think I got it. It's RFLP. I initally thought it was a distractor because I had the same reasoning Robin did. But there's no abnormality because the DNA probe is hybridized to only the 4kb section! We will NOT see a 6kb band. THe dad is normal because he doesn't have the restriction enzyme site.
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| docarchana
Forum Guru
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for these type of qs, if i see souther blot, i will blindly put RFLP
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| twesting2173
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can somone pleae expalin to me how to read thses gels? whu are two rows being run? i thought oyu just take hte dna, chop it up iwht nucleases and run it. why are there two rows? i HATE THIS STUFF. i'll probaly just skip it on my test. any help woudl be appreciated.
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| drmike11
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The first sentence is misleading! It starts by talking about a single person, but the question is about the experiment which will allow you to study the RFLP in a single person. Note that the question deals with an experiment involving 2 unrelated people.
RFLP in this case does not tell you about the phenotype or if there is an abnormal genotype; both the mom and dad could very well be normal since we all have RFLPs in our gene. If the gel electrophoresis had been of their offspring's DNA, recombination would have explained the results as the child would have inherited 1 ch 7 from mom and 1 from dad.
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