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Old 08-12-2012
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DNA Mechanism of Insertion Mutation!

Two patients with hemophilia A have been found in which the disease is due to the de novo insertion of an L1 LINES into exon 14 of the factor VIII gene during embryogenesis or maternal oogenesis. Although L1 LINES are common within the human genome, almost all of those carried in humans today are unable to move. Which of the following is most likely a characteristic of the very rare insertion that created hemophilia in these two patients?

A. DNA polymerase delta activity was required to insert the LINE sequence in the new site.
B. Homologous DNA recombination was required to insert the LINE sequence in the new site.
C. RNA polymerase II activity was required to insert the LINE sequence in the new site.
D. RNA polymerase III activity was required to insert the LINE sequence in the new site.
E. Transposase activity excised the LINE from its previous location and inserted into the exon.
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Old 08-12-2012
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Default Can someone explain

personally i didn't even understood question. So answers with brief explanation will be nice.
Thanks
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Old 08-12-2012
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Default my answer

I think it's C. RNA polymerase II activity was required to insert the LINE sequence in the new site.
bc RNA polymerase II was neccesary for LINE duplication and insertion afterwards
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Old 08-12-2012
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will go with A ,need answer plz
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Old 08-13-2012
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stuck between a and e......good question
waiting for answer.............!!!
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Old 08-14-2012
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Default ?

what's the answer?
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Old 08-16-2012
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Wink Answer is C

L1 LINE sequence are long interspersed repetitive elements (LINES) specific to humans and are present in about 100,000 copies dispersed throughout the human genome as a result of retrotransposon activity. The L1 insertions in these patients were identified as resulting from activity of a retrotransposable element on chromosome 22. In the currently accepted model of L1 dispersal, the retrotransposon is transcribed by RNA polymerase II, then the mRNA is reverse transcribed into the L1 double- stranded DNA and inserted into the genome. Retrotransposons contain at least once open reading frame (ORF), which is presumed to code for the enzymatic activities needed for synthesis and insertion of the L1 LINE.

Hope now you guys understood why i asked for your explanation. For me explanation is more confusing then question.
I am bit lazy to write about other options. If you guys want to know about any particular option please let me know. Thanks.
Ya further discussion about this explanation will also be appreciated. thanks
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Old 08-16-2012
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Quote:
Originally Posted by Casandra View Post
I think it's C. RNA polymerase II activity was required to insert the LINE sequence in the new site.
bc RNA polymerase II was neccesary for LINE duplication and insertion afterwards
you came to answer by reasoning than why you didn't considered A ?

and if you read it than please tell me where :sorry:
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