can someone explain this Q please

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can someone explain this Q please

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rsvr
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05/19/08 - 05:45 PM

Q: A 12 yr old boy has symptoms of wilsons disease. mutation in 5' UTR region of the gene is assoc with the disease . Another gene X was discovered on the opposite non coding strand. translation start codon of the disease gene is near the 1st exon of gene X. The polymorphism will be complementary to
A -1st intron of gene X
B-1st exon of gene X
C-last intron of gene X
D-last exon of gene X
E-5' UTR of gene X
F-3' UTR of gene X

sigh
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05/21/08 - 03:37 PM

Is it A?

rsvr
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05/23/08 - 10:31 PM

yes it is A , would you be kind enough to explain why it is A please thanks

taipei817
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05/24/08 - 07:58 PM

interesting question but seems a little unclear...
'near the first exon'. is it on it? upstream to it? downstream to it? the introns and exons may have variable lengths as well. confused

Ig F
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05/29/08 - 04:23 AM

what made u say that its A...plz explain....

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Yulik08
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06/05/08 - 08:54 AM

Let`s think that way. They said - "uncording" , so B and D is out, cz ther are a part of cording region. E - is also out, cz this is about first abnormality. A, C and F left. 5`UTR is the starting untr. region 3` UTR is the ending. They said opposed to 5`UTR, so it can be F, but then they said - translation start codon of the disease gene is near the 1st exon of gene X. i might be wrong, but i think it means that desease gene, may be 5`UTR is near the exon 1 of the gene X after which intron 1 follows, which is nontranslating, so answer is A. I dunno may be i`m wrong, but this is how i understood this q raised eyebrow

cherryho
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06/05/08 - 02:48 PM

Make a diagram

[ 5' UTR coding str ] ATG
________*__ _________!________
------------------------------------------
???????????????? [ Ex1 non-coding str]

_ coding str (disease gene); ---- non-coding str (gene X)
* disease mutation
! start codon

The Q is what should region ? be. most likely intron 1

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sigh
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07/29/08 - 08:58 AM

Sorry to late to replay but Cherryto thinking is the same like mine...

drsumedha
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09/05/08 - 09:40 PM

(intron1 ) (exon 1) (5'UTR)
GENE X 5' --------/----------/--------------/---------------------3'

DIS. GENE 3'--------/----------/--------------/-------------/-----5'
(TATA) (5' UTR) * (exon1) (intron1)

* (start codon) = at the end of exon1 of GENE Xsince the mutation is in 5'UTR of dis gene, the polymorphism is complementary to 1st intron of gene x.. So A is the answer

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