Fragile X sydrome

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Fragile X sydrome

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5 Posts

Hox
Forum Newbie

Topics: 8
Posts: 19

10/03/06 - 08:13 AM

Triplet repeat expansions (CGG) in Friagile X syndrome interferes by?
A.decreasing mRNA synthesis
B.increasing mRNA synthesis
C.creating splicing defect
D.? smiling face

blueocean
Forum Senior
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Topics: 15
Posts: 195

10/03/06 - 05:04 PM

A- When more than 200 CGG repeats are present, there is a high likelihood that the promoter region of the FMR-1 gene will be hypermethylated. When hypermethylation occurs, the enzyme necessary for transcription is unable to bind to the promoter region and initiate transcription. The end result is that no messenger RNA is produced, a condition referred to as ³transcriptional silencing² of a gene.

Hox
Forum Newbie

Topics: 8
Posts: 19

10/04/06 - 10:15 PM

Thank you blueocean.

young_doc
Forum Guru
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Topics: 55
Posts: 732

10/05/06 - 05:30 PM

good stuff..thanks!

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ManuNastai
Transilvanian..
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Topics: 55
Posts: 838

10/09/06 - 03:07 AM

nice.. didn't know that

thanks

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