Rett Syndrome Research Articles

The RETT syndrome, from clinics to genetics

The RETT syndrome, from clinics to genetics

EPH196 Prevalence of GI Comorbidities by Age Group Among Patients With Rett Syndrome: An Analysis of Coded EHR and Pharmacy Data and Clinical Notes

EPH196 Prevalence of GI Comorbidities by Age Group Among Patients With Rett Syndrome: An Analysis of Coded EHR and Pharmacy Data and Clinical Notes

CO68 Gastrointestinal Manifestations and Incontinence Products in the Real World Among Patients with Rett Syndrome in the United States

CO68 Gastrointestinal Manifestations and Incontinence Products in the Real World Among Patients with Rett Syndrome in the United States

The Heart of Rett Syndrome: A Quantitative Analysis of Cardiac Repolarization.

Rett syndrome (RTT) is a developmental encephalopathy disorder that is associated with a high incidence of sudden death presumably from cardiorespiratory etiologies. Electrocardiogram (ECG) abnormalities, such as prolonged heart-rate corrected QT (QTc) interval, are markers of cardiac repolarization and are associated with potentially lethal ventricular arrhythmias. This study investigates the cardiac repolarization characteristics of RTT patients, including QTc and T-wave morphology characteristics. A retrospective quantitative analysis on 110 RTT patients and 124 age and sex-matched healthy controls was conducted. RTT patients had longer QTc, more abnormal T-wave morphology, and greater heterogeneity of cardiac repolarization parameters compared to controls. Even RTT patients without prolonged QTc had more abnormal ECG and T-wave characteristics than controls. Among RTT patients, MECP2 patients had prolonged QTc compared to CDKL5 and FOXG1 patients. A subset of five RTT patients who died had normal QTc, but more abnormal T-wave morphology than the remaining RTT patients. Cardiac repolarization abnormalities are present in RTT patients, even without long QTc. T-wave morphology is related to RTT genotype and may be predictive of mortality. These findings could be used to help the management and monitoring of RTT patients.

Asiaticoside A, promising agent to revert Rett Syndrome – Preliminary study results

Asiaticoside A, promising agent to revert Rett Syndrome – Preliminary study results

Biochemical profiling of Rett syndrome patients from South Indian population

Biochemical profiling of Rett syndrome patients from South Indian population

“Hole” Exome Sequences: The Importance of Phenotyping to Fill the Gaps in Whole Exome Sequencing

BackgroundWhole exome sequencing (WES) is commonly used for patients with nonspecific clinical features and conditions with genetic heterogeneity. However, a nondiagnostic exome does not exclude a genetic diagnosis, so history and physical examination is crucial to selecting appropriate genetic testing. CasesWe report three patients with three recognizable phenotypes: a seven-year-old female with classic Rett syndrome; a 28-year-old male with neuropathy, ataxia, and retinitis pigmentosa; and a 16-year-old male with mosaic, segmental, paternal uniparental disomy 14 who had nondiagnostic WES. ConclusionsDespite recognizable phenotypes they had diagnostic delays due to incorrect selection of genetic testing. This case series highlights the limitations of WES and reinforces the importance of utilizing patient history and physical examination to select initial testing. We will discuss appropriate testing for these patients and a consistent diagnostic algorithm that can be applied when approaching patients with unknown or uncertain clinical presentations.

Screening of chromosomal instability and inheritance of Rett syndrome

Screening of chromosomal instability and inheritance of Rett syndrome

Sleep disorders in Rett syndrome patients from Indian population

Sleep disorders in Rett syndrome patients from Indian population

Generation of an integration-free induced pluripotent stem cell line, FJMUUHi002-A, from a Rett syndrome patient with a heterozygous mutation p. R133C in MeCP2

The human iPS cell line, hiPS-RTT (FJMUi002-A), is derived from peripheral blood mononuclear cells (PBMCs) from a 12-year-old female RTT patient carrying a heterozygous p. R133C (c.397C > T) mutation in the MeCP2 gene. The hiPS-RTT cell line was generated by non-integrative reprogramming vectors encoding OCT3/4, SOX2, KLF4, and c-MYC and was free of genomically integrated reprogramming genes. The hiPS-RTT cell line had a normal karyotype, expressed pluripotency markers, and had capacity to form three germ layers in vitro and in vivo, which offering a useful resource to study the pathogenesis and treatment strategies of RTT.

Trofinetide in Rett syndrome: A brief review of safety and efficacy.

Rett syndrome (RTT) is a rare genetic neurological disorder that primarily affects girls and is caused by mainly mutations in the methyl-CpG-binding protein 2 (MECP2) gene, leading to critical issues in normal brain function. The condition has a global prevalence of 5 to 10 cases per 100,000 females, and there is currently no cure for RTT. However, therapy is available to manage the symptoms and improve quality of life. Trofinetide, an insulin-like growth factor 1, was originally developed as a stroke medication and progressed to Phase II clinical trials, where it exhibited favorable safety and efficacy profiles by improving several core RTT symptoms. Recently, Trofinetide received the US Food and Drug Administration (FDA) approval and orphan drug designation for the treatment of RTT, making it the first approved drug for this rare genetic disorder. It has also shown to be safe, well-tolerated and with no known drug interactions. These findings suggest that Trofinetide is a promising treatment option for individuals with RTT.

RETT SYNDROME: A CASE REPORT

RETT syndrome is a rare,genetic neurodevelopmental disorder that mainly affect girls, at the first 6 months of live the child have a normal psychomotor and cognitive development, then appears a psychomotor regression with loss of hand use and the appearance of manual stereotypies. This syndrome is essentially related to a mutation in the MECP2 gene. We report the case of an 8-year-old girl with RETT syndrome, who showed normal neurological development up to the age of 8 months, with psychomotor regression and manual stereotypy, and no other neurological signs, thus, no epileptic seizures or respiratory disorders such as hyperpnea. Electroencephalography and genetic studies were in favor of RETT syndrome.

Brain organoids: A revolutionary tool for modeling neurological disorders and development of therapeutics.

Brain organoids are self-organized, three-dimensional (3D) aggregates derived from pluripotent stem cells that have cell types and cellular architectures resembling those of the developing human brain. The current understanding of human brain developmental processes and neurological disorders has advanced significantly with the introduction of this in vitro model. Brain organoids serve as a translational link between two-dimensional (2D) cultures and in vivo models which imitate the neural tube formation at the early and late stages and the differentiation of neuroepithelium with whole-brain regionalization. In addition, the generation of region-specific brain organoids made it possible to investigate the pathogenic and etiological aspects of acquired and inherited brain disease along with drug discovery and drug toxicity testing. In this review article, we first summarize an overview of the existing methods and platforms used for generating brain organoids and their limitations and then discuss the recent advancement in brain organoid technology. In addition, we discuss how brain organoids have been used to model aspects of neurodevelopmental and neurodegenerative diseases, including autism spectrum disorder (ASD), Rett syndrome, Zika virus-related microcephaly, Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD).

LTP is Absent in the CA1 Region of the Hippocampus of Male and Female Rett Syndrome Mouse Models

Rett syndrome (RTT) is a debilitating neurodevelopmental disorder caused by mutations in the X-linked methyl-CpG-binding protein 2 (MeCP2) gene, resulting in severe deficits in learning and memory. Alterations in synaptic plasticity have been reported in RTT, however most electrophysiological studies have been performed in male mice only, despite the fact that RTT is primarily found in females. In addition, most studies have focused on excitation, despite the emerging evidence for the important role of inhibition in learning and memory. Here, we performed an electrophysiological characterization in the CA1 region of the hippocampus in both males and females of RTT mouse models with a focus on neurogliaform (NGF) interneurons, given that they are the most abundant dendrite-targeting interneuron subtype in the hippocampus. We found that theta-burst stimulation (TBS) failed to induce long-term potentiation (LTP) in either pyramidal neurons or NGF interneurons in male or female RTT mice, with no apparent changes in short-term plasticity (STP). This failure to induce LTP was accompanied by excitation/inhibition (E/I) imbalances and altered excitability, in a sex- and cell-type specific manner. Specifically, NGF interneurons of male RTT mice displayed increased intrinsic excitability, a depolarized resting membrane potential, and decreased E/I balance, while in female RTT mice, the resting membrane potential was depolarized. Understanding the role of NGF interneurons in RTT animal models is crucial for developing targeted treatments to improve cognition in individuals with this disorder.

Bone Fracture in Rett Syndrome: Mechanisms and Prevention Strategies.

The present study aimed to evaluate the burden and management of fragility fractures in subjects with Rett syndrome. We searched all relevant medical literature from 1 January 1986 to 30 June 2023 for studies under the search term "Rett syndrome and fracture". The fracture frequency ranges from a minimum of 13.9% to a maximum of 36.1%. The majority of such fractures occur in lower limb bones and are associated with low bone mineral density. Anticonvulsant use, joint contractures, immobilization, low physical activity, poor nutrition, the genotype, and lower calcium and vitamin D intakes all significantly impair skeletal maturation and bone mass accrual in Rett syndrome patients, making them more susceptible to fragility fractures. This review summarizes the knowledge on risk factors for fragility fracture in patients with Rett syndrome and suggests a possible diagnostic and therapeutic care pathway for improving low bone mineral density and reducing the risk of fragility fractures. The optimization of physical activity, along with adequate nutrition and the intake of calcium and vitamin D supplements, should be recommended. In addition, subjects with Rett syndrome and a history of fracture should consider using bisphosphonates.

Trofinetide Treatment Demonstrates a Benefit Over Placebo for the Ability to Communicate in Rett Syndrome

BackgroundTrofinetide was approved by the US Food and Drug Administration for the treatment of Rett syndrome (RTT) in March 2023. Benefiting the ability to communicate in RTT is often identified as the most important caregiver goal for new therapies. This analysis reports the communication-related end points from the phase 3 LAVENDER study of trofinetide in RTT. MethodsFemales with RTT, aged five to 20 years, were randomized 1:1 to trofinetide or placebo for 12 weeks. Secondary efficacy end points related to communication were based on change from baseline to week 12 and included the caregiver-rated Communication and Symbolic Behavior Scales Developmental Profile™ Infant-Toddler Checklist (CSBS-DP-IT) Social Composite score (key secondary end point; scores ranged from 0 to 26 [higher scores indicated better communication]) and novel clinician rating scales (0 [normal] to 7 [severe impairment]) measuring the ability to communicate choices nonverbally (RTT-COMC) and verbally (RTT-VCOM). ResultsTrofinetide demonstrated a statistically significant difference versus placebo for the CSBS-DP-IT Social Composite score (least squares mean [LSM] difference = 1.0; 95% confidence interval [CI], 0.3 to 1.7; P = 0.0064; Cohen's d effect size = 0.43) and a nominally significant difference for the RTT-COMC (LSM difference: −0.3; 95% CI, −0.6 to −0.0; P = 0.0257; Cohen's d effect size = 0.36). As expected, there was no difference for the RTT-VCOM. ConclusionsSignificant treatment benefit for trofinetide versus placebo was observed in scales measuring the ability to communicate. These scales may be appropriate for future clinical studies in RTT and other neurodevelopmental disorders.

Real-world clinical management of individuals with Rett syndrome: a physician survey

BackgroundRett syndrome (RTT) is a severe neurodevelopmental disorder. Management strategies are heterogeneous with no clear definition of success. This study describes physician decision-making regarding diagnosis, therapeutic goals, and management strategies to better understand RTT clinical management in the US.MethodsThis study was conducted among practicing physicians, specifically neurologists and pediatricians in the US with experience treating ≥2 individuals with RTT, including ≥1 individuals within the past two years. In-depth interviews with five physicians informed survey development. A cross-sectional survey was then conducted among 100 physicians.ResultsNeurologists had treated more individuals with RTT (median: 12 vs. 5, p < 0.001) than pediatricians throughout their career and were more likely to report being “very comfortable” managing RTT (31 vs. 4%, p < 0.001). Among physicians with experience diagnosing RTT (93%), most evaluated symptoms (91%) or used genetic testing (86%) for RTT diagnoses; neurologists used the 2010 consensus diagnostic criteria more than pediatricians (54 vs. 29%; p = 0.012). Improving the quality of life (QOL) of individuals with RTT was the most important therapeutic goal among physicians, followed by improving caregivers’ QOL. Most physicians used clinical practice guidelines to monitor the progress of individuals with RTT, although neurologists relied more on clinical scales than pediatricians. Among all physicians, the most commonly treated symptoms included behavioral issues, epilepsy/seizures, and feeding issues. Management strategies varied by symptom, with referral to appropriate specialists being common across symptoms. A large proportion of physicians (37%) identified the lack of novel therapies and reliance on symptom-specific management as an unmet need.ConclusionAlthough most physicians had experience and were comfortable diagnosing and treating individuals with RTT, better education and support among pediatricians is warranted. Additionally, novel treatments that target multiple symptoms associated with RTT could reduce the burden and improve the QOL of individuals with RTT and their caregivers.

Melatonin in Neurodevelopmental Disorders: A Critical Literature Review.

The article presents a review of the relationships between melatonin and neurodevelopmental disorders. First, the antioxidant properties of melatonin and its physiological effects are considered to understand better the role of melatonin in typical and atypical neurodevelopment. Then, several neurodevelopmental disorders occurring during infancy, such as autism spectrum disorder or neurogenetic disorders associated with autism (including Smith-Magenis syndrome, Angelman syndrome, Rett's syndrome, Tuberous sclerosis, or Williams-Beuren syndrome) and neurodevelopmental disorders occurring later in adulthood like bipolar disorder and schizophrenia, are discussed with regard to impaired melatonin production and circadian rhythms, in particular, sleep-wake rhythms. This article addresses the issue of overlapping symptoms that are commonly observed within these different mental conditions and debates the role of abnormal melatonin production and altered circadian rhythms in the pathophysiology and behavioral expression of these neurodevelopmental disorders.

The Effect of Caregiver-Implemented Training on Augmentative Alternative Communication Use by Individuals with Rett Syndrome: Remote Coaching via Telehealth

ABSTRACT Limited published literature exists demonstrating functional relations between idiosyncratic responses or augmentative alternative communication (AAC) and social reinforcement for individuals with Rett syndrome. In this study, six females with Rett syndrome ages 2–25 demonstrated requesting for preferred items using both idiosyncratic responses (e.g, looking, reaching) and AAC (e.g. single response microswitches). Researchers connected remotely via telehealth to coach caregivers to implement all sessions in home environments. Researchers individualized response prompt delays during AAC sessions (request/mand training) based on each participants’ latency to respond during baseline. Implications for practice and directions for future research are discussed.

Trofinetide-a new chapter in rett syndrome's treatment.

Trofinetide is the first drug approved by the FDA to treat Rett Syndrome in children aged 2years or above. The drug significantly improved Rett syndrome behavioral scores Rett syndrome behavioral questionnaire in clinical studies. Although further research is needed to assess potential adverse events, Trofinetide's notable efficacy signifies a significant advancement in Rett syndrome treatment, offering a new therapeutic avenue with the potential to ameliorate the condition.