CGG expansions in the 5' untranslated region 5'UTR of FMR1 cause which of the following?

Question

Quizplus · Accepted Answer

CGG expansions in the 5' untranslated region (5'UTR) of the FMR1 gene lead to repeat methylation and transcriptional silencing of the gene, which is associated with Fragile X syndrome. This does not lead to the expression of polyglutamine sequences, which is associated with other types of repeat expansion disorders. The mechanism involves a loss of function due to the inability to produce the FMRP protein, rather than a gain of function toxicity of the FMR1 mRNA itself.

CGG Expansions in the 5' Untranslated Region 5'UTR of FMR1