Relationships between Fragile X Mental Retardation 1 (FMR1) mRNA levels in blood and intragenic FMR1 CGG triplet expansions support the pathogenic role of RNA gain of function toxicity in premutation (PM: 55-199 CGGs) related disorders. Real-time PCR (RT-PCR) studies reporting these findings normalised FMR1 mRNA level to a single internal control gene called β-glucuronidase (GUS). This study ev...

BACKGROUND Fragile X syndrome (FXS), a common cause of intellectual disability and autism, results from the expansion of a CGG-repeat tract in the 5' untranslated region of the FMR1 gene to >200 repeats. Such expanded alleles, known as full mutation (FM) alleles, are epigenetically silenced in differentiated cells thus resulting in the loss of FMRP, a protein important for learning and memory. ...

El síndrome X frágil es la causa más frecuente de retraso psicomotor vinculado a cromosoma en niños, con una prevalencia 1 : 5.000 hombres y 4.000 - 8.000 mujeres. Además, hereditaria asociada al del espectro autista. Esta patología posee como base etiológica expansión triplete CGG el extremo distal gen FMR1, lo que silenciamiento mismo. Los pacientes afectados este suelen padecer problemas con...

STUDY QUESTION Can we confirm in our population whether FMRI low sub-genotypes are associated with BRCA1/2 mutations, as recently proposed? SUMMARY ANSWER Our results indicate that the distribution of the FMR1 sub-genotypes in female BRCA1/2-mutation carriers is significantly different from what has been reported previously and resembles that of the control population. FMRI low sub-genotypes ...

Fragile X syndrome is a developmental disorder that affects sensory systems. A null mutation of the Fragile X Mental Retardation protein 1 (Fmr1) gene in mice has varied effects on developmental plasticity in different sensory systems, including normal barrel cortical plasticity, altered ocular dominance plasticity and grossly impaired auditory frequency map plasticity. The mutation also has di...

Fragile X syndrome, a common form of inherited mental retardation, is mainly caused by massive expansion of CGG triplet repeats located in the 5'-untranslated region of the fragile X mental retardation-1 ( FMR1 ) gene. In patients with fragile X syndrome, the expanded CGG triplet repeats are hypermethylated and the expression of the FMR1 gene is repressed, which leads to the absence of FMR1 pro...

Subcellular targeting and local translation of mRNAs are critical for axon development. However, the precise local control of mRNA translation requires investigation. We report that the Fmr1-encoded protein, FMRP-mediated axonal delivery of miR-181d negatively regulates axon elongation by locally targeting the transcripts of MAP1B (Map1b) and calmodulin (Calm1) in primary sensory neurons. miR-1...

Excessive mRNA translation downstream of group I metabotropic glutamate receptors (mGlu1/5) is a core pathophysiology of fragile X syndrome (FX); however, the differentially translating mRNAs that contribute to altered neural function are not known. We used translating ribosome affinity purification (TRAP) and RNA-seq to identify mistranslating mRNAs in CA1 pyramidal neurons of the FX mouse mod...

The purpose of this article is to provide an overview of the behavioral phenotype of FMR1 mutations, including fragile X syndrome (FXS) in order to better understand the clinical involvement of individuals affected by mutations in this gene. FXS is associated with a wide range of intellectual and behavioral problems, some relatively mild and others quite severe. FXS is the most common cause of ...