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Old 03-29-2012
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Arrow NBME 12 Block 3

can anyone explain to me how to solve this question as I found it too much complicated???
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Old 03-29-2012
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Default UAA (U are away = stop codon

this is such a headache problem...

I really hope the explanations help you... =)

B. G --> A (346)

b-thalassemia is an incomplete globin chain that work inappropriately.

if you change G by A at position 246 , the RNA will have an stop codon dna ATT--> RNA UAA (U are away = stop codon

the change then transcript this DNA to mRNA and you will find out a stop codon (in thalassemia that what makes the globin not functional its translation is not completed)
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Old 09-24-2013
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Dear what he said above is completely wrong explanation for the correct answer

yes the answer is B but the explanation he mentioned is not correct

The questions speaks about B-thalassesmia which is due to splice site mutation

so you have to look at a point of exon intron binding that's mutated which will be your correct answer and that's choice B

all other choices mutation if you examine them you can easily eliminate them if we don't know anything abt such concept, but we are lazy to try

hope i helped, all the best with your studies !
" The sign on the door to success says, 'PUSH'."
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