Which of the following mechanisms in fragile X syndrome (FXS) leads to expression of the disorder?
A)Trinucleotide repeat sequences interspersed with the exons of the FMR1 gene, resulting in the production of an abnormal protein
B)Trinucleotide repeat sequences causing methylation of the FMR1 gene, thus silencing its expression
C)Increased production of microRNA molecules that interfere with the transcription of the FMR1 gene
D)Increased production of microRNA molecules that interfere with the translation of the FMR1 gene

Question

Quizplus · Accepted Answer

In FXS, the FMR1 gene-coding regions are normal, but the gene's expression is silenced by large numbers of the trinucleotide sequence of CGG being repeated within the noncoding regions of the gene.

Which of the Following Mechanisms in Fragile X Syndrome (FXS)