Fragile-X-associated tremor/ataxia syndrome (FXTAS) is a progressive neurodegenerative disorder associated with the FMR1 gene premutation, characterized by the presence of 55 to 200 CGG triplet repeat expansions. Although the initial symptoms of FXTAS typically manifest in males around the age of 60 with motor symptoms and cognitive deficits, the presentation and progression in females differ. Women, in fact, exhibit a higher prevalence of neuropsychiatric symptoms, with an earlier onset compared to the motor symptoms observed in men. The following article reports on ten cases of women with a diagnosis of FMR1 gene premutation, originating from two medical centers. All the women in the study exhibited neuropsychiatric symptoms and subtle neurological signs as common features. Symptoms typically observed in the male population, such as tremors and cerebellar ataxia, were either absent or significantly reduced in the female cohort. Conversely, there was a higher prevalence of neuropsychiatric symptoms among the women. Neurocognitive impairment was only minimally evident, with mild executive dysfunction and memory complaints noted in a subset of cases. For this reason, we propose the terminology preFXTAS or prodromic FXTAS to define a clinical presentation in women characterized by early manifestations of FXTAS that do not entirely fulfill the established diagnostic criteria but exhibit MRI evidence of white matter alterations suggesting the initiation of the disease process. The study underscores the importance of establishing new diagnostic criteria for FXTAS and, at the same time, developing new biomarkers and interview checklists/assessment scales dedicated to females.

Fragile X (FMR1) premutation is a common mutation that affects about 1 in 200 females and 1 in 450 males and can lead to the development of fragile-X-associated tremor/ataxia syndrome (FXTAS). Although there is no targeted, proven treatment for FXTAS, research suggests that sulforaphane, an antioxidant present in cruciferous vegetables, can enhance mitochondrial function and maintain redox balance in the dermal fibroblasts of individuals with FXTAS, potentially leading to improved cognitive function. In a 24-week open-label trial involving 15 adults aged 60–88 with FXTAS, 11 participants successfully completed the study, demonstrating the safety and tolerability of sulforaphane. Clinical outcomes and biomarkers were measured to elucidate the effects of sulforaphane. While there were nominal improvements in multiple clinical measures, they were not significantly different after correction for multiple comparisons. PBMC energetic measures showed that the level of citrate synthase was higher after sulforaphane treatment, resulting in lower ATP production. The ratio of complex I to complex II showed positive correlations with the MoCA and BDS scores. Several mitochondrial biomarkers showed increased activity and quantity and were correlated with clinical improvements.

Background: Fragile X mental retardation 1 (FMR1) premutation can cause developmental problems including autism spectrum disorder (ASD), social anxiety, depression, and attention deficit hyperactivity disorder (ADHD). These problems fall under an umbrella term of Fragile X‐associated Neuropsychiatric Disorders (FXAND) and is separate from Fragile X‐associated Tremor/Ataxia syndrome (FXTAS), a neurodegenerative disorder.Methods/Clinical Case: A 26‐year‐old Caucasian male with the Fragile X premutation who presented with multiple behavior and emotional problems including depression and anxiety at 10 years of age. He was evaluated at 13, 18, and 26 years old with age‐appropriate cognitive assessments, psychiatric evaluations, and an MRI of the brain.Results: The Autism Diagnostic Observation Scale (ADOS) was done at 13 years old and showed the patient has autism spectrum disorder (ASD). An evaluation at 18 years old showed a full‐scale IQ of 64. A Kiddie Schedule for Affective Disorders and Schizophrenia (K‐SADS) performed at 26 years old confirmed the previous impression of social anxiety disorder, agoraphobia disorder, and selective mutism. His MRI acquired at 26 years old showed enlarged ventricles, increased frontal subarachnoid spaces, and hypergyrification.Conclusion: This is an exemplary case of an FMR1 premutation carrier with significant psychiatric and cognitive issues that demonstrates Fragile X‐associated Neuropsychiatric Disorders (FXAND) as separate from the other well‐known premutation disorders.

Fragile X syndrome (FXS) is the leading inherited cause of intellectual disability (ID) and single gene cause of autism. Although most patients with FXS and the full mutation (FM) have complete methylation of the fragile X messenger ribonucleoprotein 1 (FMR1) gene, some have mosaicism in methylation and/or CGG repeat size, and few have completely unmethylated FM alleles. Those with a complete lack of methylation are rare, with little literature about the cognitive and behavioral phenotypes of these individuals. A review of past literature was conducted regarding individuals with unmethylated and mosaic FMR1 FM. We report three patients with an unmethylated FM FMR1 alleles without any behavioral or cognitive deficits. This is an unusual presentation for men with FM as most patients with an unmethylated FM and no behavioral phenotypes do not receive fragile X DNA testing or a diagnosis of FXS. Our cases showed that mosaic males with unmethylated FMR1 FM alleles may lack behavioral phenotypes due to the presence of smaller alleles producing the FMR1 protein (FMRP). However, these individuals could be at a higher risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS) due to the increased expression of mRNA, similar to those who only have a premutation.

The study’s aim was to evaluate electroretinographic (ERG) alterations in Fragile X syndrome (FXS), FMR1 premutation carriers, and controls, and to explore correlations with peripheral blood FMRP expression levels and behavioral outcomes. ERG recordings were obtained using a handheld device across three stimulus protocols in 43 premutation carriers, 39 individuals with FXS, and 23 controls. Peripheral blood FMRP expression levels were quantified using TR-FRET (Time-Resolved Fluorescence Resonance Energy Transfer). Correlations were assessed with cognitive and behavioral measures including IQ (Intelligence Quotient), ABC_FX (Aberrant Behavior Checklist for Fragile X Syndrome), SNAP-IV (Swanson, Nolan, and Pelham Teacher and Parent Rating Scale), SEQ (Sensory Experiences Questionnaire), ADAMS (Anxiety, Depression, and Mood Scale), and the Vineland III Adaptive Behavior Scale standard score. Significant group differences were observed in multiple ERG parameters, particularly in 2 Hz b-wave amplitude (p = 0.0081), 2 Hz b-wave time to peak (p = 0.0164), 28.3 Hz flash combined amplitude (p = 0.0139), 3.4 Hz red/blue flash b-wave amplitude (p = 0.0026), and PhNR amplitude (p = 0.0026), indicating both outer and inner retinal dysfunction in FXS and premutation groups. Despite high test–retest reliability for ERG (ICC range = 0.71–0.92) and FMRP (ICC = 0.70), no correlation was found between ERG metrics and FMRP or behavioral measures. However, FMRP levels strongly correlated with IQ (ρ = 0.69, p < 0.0001) and inversely with behavioral impairment [ABC_FX (ρ = −0.47, p = 0.0041), SNAP-IV (ρ = −0.48, p = 0.0039), SEQ (ρ = −0.43, p = 0.0146), and the Vineland III standard score (ρ = 0.56, p = 0.0019)]. ERG reveals distinct retinal functional abnormalities in FMR1-related conditions but does not correlate with peripheral FMRP expression levels, highlighting the need for multimodal biomarkers integrating radiological, physiological, behavioral, and molecular measures.

Fragile X syndrome (FXS) presents with autism spectrum disorder (ASD), intellectual disability, developmental delay, seizures, hypotonia during infancy, joint laxity, behavioral issues, and characteristic facial features. The predominant mechanism is due to CGG trinucleotide repeat expansion of more than 200 repeats in the 5′UTR (untranslated region) of FMR1 (Fragile X Messenger Ribonucleoprotein 1) causing promoter methylation and transcriptional silencing. However, not all patients presenting with the characteristic phenotype and point/frameshift mutations with deletions in FMR1 have been described in the literature. It is believed that < 1% of cases are caused by point mutations. Genetic and functional testing of point mutations in FXS has yielded insights on KH domain RNA‐binding properties of FMRP (Fragile X Messenger Ribonucleoprotein Protein) and nuclear export of the protein. Here, we report a c.1599_1601del p.Arg534del novel mutation in FMR1 with homozygous C677T MTHFR polymorphism in a 12‐year‐old boy. He presents with unique phenotype of FXS with ASD, developmental delay, nonverbal learning disorder (NVLD), overall IQ in the 5 ^th percentile with above average verbal IQ (66 ^th percentile), difficulties with quantitative reasoning, dyspraxia, below average visual‐spatial skills (2 ^nd percentile), difficulty with social pragmatics and social understanding, and executive dysfunction. He has a strong aptitude for music and exceptional aural skills. Identification of novel variants has helped in understanding functional aspects of FMRP. In addition, it aids families in genetic counseling and in administering therapies for children with FXS who present with atypical features.