Public Health Literature Review of Fragile X Syndrome

"We are not a typical family anymore": Exploring the experiences and support needs of fathers of children with Fragile X syndrome in Australia

A diagnosis of the X-linked condition Fragile X syndrome (FXS) in a child commonly reveals the mother's carrier status. Previous research focused on the genetic counseling process for the child and maternal family, despite calls for more research on the support needs of fathers. This study explored experiences and support needs of fathers at least 1 year after their child's FXS diagnosis to understand barriers and enablers and optimize health outcomes for the family. In-depth interviews were conducted with 11 fathers recruited through the Australian Genetics of Learning Disability Service and the Fragile X Association. Deidentified transcripts were analyzed using thematic analysis guided by an inductive approach. Four themes emerged: (1) making life easier through understanding-yesterday and today, (2) the path to a new normal-today and tomorrow, (3) seeking information and support, and (4) what men want. Fathers reported diagnostic odysseys, postdiagnostic grief, and challenges adjusting. They highlighted difficulties in understanding their child's unique behaviors and needs, responding to their partner's psychological support needs, planning for their child's future, and navigating complex health and disability systems. Participants suggested health professionals facilitate father-to-father support and psychological counseling. These findings highlight the unmet needs of fathers and suggest that a strengths-based approach is critically important given the recognized mental health impact.

Unexplored power of CRISPR-Cas9 in neuroscience, a multi-OMICs review

The neuroscience and neurobiology of gene editing to enhance learning and memory is of paramount interest to the scientific community. The advancements of CRISPR system have created avenues to treat neurological disorders by means of versatile modalities varying from expression to suppression of genes and proteins. Neurodegenerative disorders have also been attributed to non-canonical DNA secondary structures by affecting neuron activity through controlling gene expression, nucleosome shape, transcription, translation, replication, and recombination. Changing DNA regulatory elements which could contribute to the fate and function of neurons are thoroughly discussed in this review. This study presents the ability of CRISPR system to boost learning power and memory, treat or cure genetically-based neurological disorders, and alleviate psychiatric diseases by altering the activity and the irritability of the neurons at the synaptic cleft through DNA manipulation, and also, epigenetic modifications using Cas9. We explore and examine how each different OMIC techniques can come useful when altering DNA sequences. Such insight into the underlying relationship between OMICs and cellular behaviors leads us to better neurological and psychiatric therapeutics by intelligently designing and utilizing the CRISPR/Cas9 technology.

Language Skills Influence Transition Planning in Adolescents With Fragile X Syndrome

Individuals with fragile X syndrome (FXS) and their parents have a range of experiences navigating the crucial transition period between adolescence and adulthood. Semistructured interviews of 47 mothers of adolescents with FXS (mean child age = 15.89 years) were analyzed to identify mothers' changing expectations during the adolescent period and parent goals related to work and postsecondary education. Mothers' work and education goals were explored in relation to child factors such as language skills and autism characteristics. Lower language skills were associated with lower likelihood of reporting vocational goals. Results suggest that adolescents with FXS with lower language ability are less likely to have vocational plans for adulthood during this critical period and may need greater transition planning assistance.

Cognition, academic achievement, and adaptive behavior in school-aged girls with fragile X syndrome

BACKGROUND

Fragile X syndrome (FXS) is the leading monogenic cause of intellectual disability and autism in males and females. Females with FXS typically display a milder cognitive phenotype than males, despite experiencing significant developmental, behavioral, and social-emotional issues.

AIMS

To measure and distinguish the cognitive-behavioral profile of girls with FXS relative to verbal IQ-matched peers.

METHODS AND PROCEDURES

Ninety-seven participants (NFXS=55, Ncomparison=42) six to 16 years of age completed assessments evaluating cognition, academic achievement, and adaptive behavior. The comparison group consisted of age-, sex-, and verbal IQ-matched peers.

OUTCOMES AND RESULTS

Consistent with previous studies, the FXS group demonstrated mean cognitive skills, academic achievement, and adaptive behavior in the borderline to low average range. On average, the FXS group showed poorer nonverbal reasoning, visual pattern recognition, verbal abstraction, math abilities, attention, inhibitory control, and working memory than the comparison group. There were no significant group differences in adaptive behavior. Different patterns of associations between cognition and selected outcomes emerged in each group.

CONCLUSIONS AND IMPLICATIONS

Results highlight the importance of identifying specific cognitive-behavioral profiles in girls with FXS to inform more targeted interventions for optimizing outcomes and quality of life in this population.

Brain Mitochondrial Bioenergetics in Genetic Neurodevelopmental Disorders: Focus on Down, Rett and Fragile X Syndromes

Mitochondria, far beyond their prominent role as cellular powerhouses, are complex cellular organelles active as central metabolic hubs that are capable of integrating and controlling several signaling pathways essential for neurological processes, including neurogenesis and neuroplasticity. On the other hand, mitochondria are themselves regulated from a series of signaling proteins to achieve the best efficiency in producing energy, in establishing a network and in performing their own de novo synthesis or clearance. Dysfunctions in signaling processes that control mitochondrial biogenesis, dynamics and bioenergetics are increasingly associated with impairment in brain development and involved in a wide variety of neurodevelopmental disorders. Here, we review recent evidence proving the emerging role of mitochondria as master regulators of brain bioenergetics, highlighting their control skills in brain neurodevelopment and cognition. We analyze, from a mechanistic point of view, mitochondrial bioenergetic dysfunction as causally interrelated to the origins of typical genetic intellectual disability-related neurodevelopmental disorders, such as Down, Rett and Fragile X syndromes. Finally, we discuss whether mitochondria can become therapeutic targets to improve brain development and function from a holistic perspective.

Vector enabled CRISPR gene editing - A revolutionary strategy for targeting the diversity of brain pathologies

Brain pathologies are considered one of the greatest contributors of death and disability worldwide. Neurodegenerative Alzheimer's disease is the second leading cause of death in adults, whilst brain cancers including glioblastoma multiforme in adults, and pediatric-type high-grade gliomas in children remain largely untreatable. A further compounding issue for patients with brain pathologies is that of long-term neuropsychiatric sequela - as a symptom or arising from high dose therapeutic intervention. The major challenge to effective, low dose treatment is finding therapeutics that successfully cross the blood-brain barrier and target aberrant cellular processes, while having minimum effect on essential cellular processes, and healthy bystander cells. Following over 30 years of research, CRISPR technology has emerged as a biomedical tour de force with the potential to revolutionise the treatment of both neurological and cancer related brain pathologies. The aim of this review is to take stock of the progress made in CRISPR technology in relation to treating brain pathologies. Specifically, we will describe studies which look beyond design, synthesis, and theoretical application; and focus instead on in vivo studies with translation potential. Along with discussing the latest breakthrough techniques being applied within the CRISPR field, we aim to provide a prospective on the knowledge gaps that exist and challenges that still lay ahead for CRISPR technology prior to successful application in the brain disease treatment field.

Research Gaps in Fragile X Syndrome: An Updated Literature Review to Inform Clinical and Public Health Practice

OBJECTIVE

The phenotypic impact of fragile X syndrome (FXS) has been well-documented since the discovery of the fragile X messenger ribonucleoprotein 1 gene 30 years ago. However, gaps remain in clinical and public health research. The purpose of this literature review was to determine the extent to which these gaps have been addressed and identify targeted areas of future research.

METHODS

We conducted an electronic search of several scientific databases using a variety of key words. The search focused on 5 areas identified as research gaps by an earlier review: (1) diagnosis, (2) phenotypic presentation, (3) familial impact, (4) interventions and treatments, and (5) life span perspectives. Inclusion criteria included publication between 2014 and 2020, focus on human subjects, and publication in English. A total of 480 articles were identified, 365 were reviewed, and 112 are summarized in this review.

RESULTS

Results are organized into the following categories: (1) FXS phenotype and subtypes (FXS subtypes, medical profile, cognitive/developmental profile, social and behavioral profile); (2) needs of adults; (3) public health needs (clinical diagnosis and newborn screening, health care needs, and access); (4) treatment (treatment priorities, pharmacological treatments, and behavioral and educational interventions); and (5) families (economic burden and mother-child relationship).

CONCLUSION

Despite the progress in many areas of FXS research, work remains to address gaps in clinical and public health knowledge. We pose 3 main areas of focused research, including early detection and diagnosis, determinants of health, and development and implementation of targeted interventions.

Longitudinal PET studies of mGluR5 in FXS using an FMR1 knockout mouse model

Fragile X syndrome (FXS) is a monogenic disorder characterized by intellectual disability and behavioral challenges. It is caused by aberrant methylation of the fragile X mental retardation 1 (FMR1) gene. Given the failure of clinical trials in FXS and growing evidence of a role of metabotropic glutamate subtype 5 receptors (mGluR5) in the pathophysiology of the disorder, we investigated mGluR5 function in FMR1 Knockout (FMR1-KO) mice and age- and sex-matched control mice using longitudinal positron emission tomography (PET) imaging to better understand the disorder. The studies were repeated at four time points to examine age- and disease-induced changes in mGluR5 availability using 3-fluoro-[18F]5-(2-pyridinylethynyl)benzonitrile ([18F]FPEB). We found that the binding potential (BP) of [18F]FPEB was significantly lower in the KO mice in mGluR5-implicated brain areas including striatum, cortex, hippocampus, thalamus, and olfactory bulb. The BP also changed with age, regardless of disorder status, increasing in early adulthood in male but not in female mice before decreasing later in both sexes. The difference in mGluR5 availability between the FMR1-KO and control mice and the change in BP in the KO mice as a function of age and sex illustrate the nature of the disorder and its progression, providing mechanistic insights for treatment design.

Behavior Problems and Social Competence in Fragile X Syndrome: A Systematic Review

Fragile X syndrome (FXS) causes intellectual disability and is the known leading cause of autism. Common problems in FXS include behavior and social problems. Along with syndromic characteristics and autism comorbidity, environmental factors might influence these difficulties. This systematic review focuses on the last 20 years of studies concerning behavior and social problems in FXS, considering environmental and personal variables that might influence both problems. Three databases were reviewed, leading to fifty-one studies meeting the inclusion criteria. Attention deficit hyperactivity disorder (ADHD) problems remain the greatest behavior problems, with behavioral problems and social competence being stable during the 20 years. Some developmental trajectories might have changed due to higher methodological control, such as aggressive behavior and attention problems. The socialization trajectory from childhood to adolescence remains unclear. Comorbidity with autism in individuals with FXS increased behavior problems and worsened social competence profiles. At the same time, comparisons between individuals with comorbid FXS and autism and individuals with autism might help define the comorbid phenotype. Environmental factors and parental characteristics influenced behavior problems and social competence. Higher methodological control is needed in studies including autism symptomatology and parental characteristics. More studies comparing autism in FXS with idiopathic autism are needed to discern differences between conditions.

Psychotropic Drug Treatment Patterns in Persons with Fragile X Syndrome

Objective: Psychiatric comorbidity is common in fragile X syndrome (FXS) and often addressed through pharmacological management. Here we examine data in the Fragile X Online Registry With Accessible Research Database (FORWARD) to characterize specific symptoms being treated with psychotropic medication, patterns of medication use, as well as the influence of gender, intellectual disability (ID), age, and autism spectrum disorder (ASD) diagnosis. Methods: Data were drawn from the 975 participants who have a completed clinician form. We explored the frequency of psychotropic medication use for the following symptom clusters: attention, hyperactivity, anxiety, hypersensitivity, obsessive-compulsive disorder (OCD), mood swings, irritability/agitation, aggression, and self-injury (IAAS). Results: A majority of participants (617 or 63.3%) were taking a psychotropic medication, including investigational drugs. Medications were often targeting multiple symptoms. Psychotropic medication use was more common in males, adolescents, and those with comorbid ID and ASD. Anxiety was the most frequently targeted symptom, followed by attention-deficit/hyperactivity disorder symptoms and IAAS. Selective serotonin reuptake inhibitors (SSRIs) were the most frequently prescribed medication class among all patients (n = 266, 43%), followed by stimulants (n = 235, 38%), each with no gender difference. Antipsychotics were the third most frequently prescribed medication class (n = 205, 33%), and were more frequently prescribed to males and those with ID and ASD. Conclusions: Anxiety, attention and hyperactivity were the most common symptom targets for psychopharmacologic intervention in FXS. Our results support clinical knowledge that males with comorbid ASD and ID have a more severe presentation requiring more intervention including medications. These results highlight the need for examination of symptom overlap and interaction.

Mitochondrial bioenergetics of astrocytes in Fragile X Syndrome: new perspectives from culture conditions and sex effects

Fragile X syndrome is a genetic disorder that is characterized by a range of cognitive and behavioural deficits, including mild-moderate intellectual disability. The disease is characterized by an X-linked mutation of the Fmr1 gene, which causes silencing of the gene coding for FMRP, a translational regulator integral for neurodevelopment. Mitochondrial dysfunction has been recently associated with FXS, with reports of increases in oxidative stress markers, reactive oxygen species, and lipid peroxidation being present in brain tissue. Astrocytes, a prominent glial cell within the CNS, plays a large role in regulating oxidative homeostasis within the developing brain and dysregulation of astrocyte redox balance in FXS may contribute to oxidative stress. Astrocyte function and mitochondrial bioenergetics is significantly influenced by oxygen availability as well as circulating sex hormones; yet these parameters are rarely considered during in vitro experimentation. Given that the brain normally develops in a range of hypoxic conditions and FXS is a sex-linked genetic disorder, we investigated how different oxygen levels (normoxic versus hypoxic) and biological sex affected mitochondrial bioenergetics of astrocytes in FXS. Our results show demonstrate that both mitochondrial respiration capacity and reactive oxygen species emission are altered with Fmr1 deletion in astrocytes and these changes were dependent upon both sexual dimorphism and oxygen availability.

The Cost of Raising Individuals with Fragile X or Chromosome 15 Imprinting Disorders in Australia

The study characterised differences in costs associated with raising a child between four rare disorders and examined the associations between these costs with clinical severity. Caregivers of 108 individuals with Prader-Willi, Angelman (AS), Chromosome 15q Duplication and fragile X (FXS) syndromes completed a modified Client Services Receipt Inventory and participants completed intellectual/developmental functioning and autism assessments. AS incurred the highest yearly costs per individual ($AUD96,994), while FXS had the lowest costs ($AUD33,221). Intellectual functioning negatively predicted total costs, after controlling for diagnosis. The effect of intellectual functioning on total costs for those with AS was significantly different to the other syndromes. The study highlights the significant costs associated with these syndromes, particularly AS, linked with severity of intellectual functioning.

Pilot study of socio-emotional factors and adaptive behavior in young females with fragile X syndrome

Girls with Fragile-X-Syndrome (FXS) present high levels of social anxiety, social avoidance, extreme shyness, tendency to social isolation, poor eye contact, learning difficulties, and depression. The aims of the present study, which is based on a group of young females with FXS are: 1) to analyze the possible associations between emotion recognition, theory of mind, and social anxiety, and adaptive behavior, and emotional state; 2) to study the relationship between intelligence quotient (IQ) and adaptive behavior; and 3) to assess whether social anxiety is more prevalent in girls with FXS. The study has 40 female participants aged between 7 and 16 years (26 positive full mutation FXS and 14 as a control group). A neuropsychological assessment was conducted using the following tests: WISC-V, NEPSY-II, SENA, ADHD Rating Scale, BAS, and ABAS-II. In comparison with the control group, the group with FXS presented a greater association between IQ and self-direction ability, and between emotion recognition and leadership. The FXS group presented higher levels of social anxiety and shyness. In the group of girls with FXS, IQ may have prognostic value for both self-direction ability and social adaptation level.

Fragile X syndrome in young females: Influence of executive function on the neurocognitive profile and adaptive behavior

INTRODUCTION

The aim of this study is to describe the relationship between executive function (EF) and performance in different areas of the neurocognitive profile in young girls with Fragile-X-Syndrome (FXS).

METHOD

A neuropsychological assessment was carried out to 40 female participants aged 7-16 years (26 FXS, 14 control group).

RESULTS

Regarding intellectual ability, in the group of girls with FXS 3.84 % of the participants obtained IQ scores in the range of moderate ID (IQ 35-40 to 49), 46.15 % in the range of mild ID (IQ 50-70), 38.46 % in the borderline range (IQ 70-85), and 11.53 % within the average range (IQ > 85). EF was found to have a greater influence on adaptive behavior, arithmetic ability, theory of mind, leadership, social integration, social competence, and anxiety/shyness in the group with FXS.

CONCLUSIONS

In girls with FXS, EF showed a greater influence on adaptive behavior, arithmetic ability, and social domain.

Artificial intelligence-assisted phenotype discovery of fragile X syndrome in a population-based sample

PURPOSE

Fragile X syndrome (FXS), the most prevalent inherited cause of intellectual disability, remains underdiagnosed in the general population. Clinical studies have shown that individuals with FXS have a complex health profile leading to unique clinical needs. However, the full impact of this X-linked disorder on the health of affected individuals is unclear and the prevalence of co-occurring conditions is unknown.

METHODS

We mined the longitudinal electronic health records from more than one million individuals to investigate the health characteristics of patients who have been clinically diagnosed with FXS. Additionally, using machine-learning approaches, we created predictive models to identify individuals with FXS in the general population.

RESULTS

Our discovery-oriented approach identified the associations of FXS with a wide range of medical conditions including circulatory, endocrine, digestive, and genitourinary, in addition to mental and neurological disorders. We successfully created predictive models to identify cases five years prior to clinical diagnosis of FXS without relying on any genetic or familial data.

CONCLUSION

Although FXS is often thought of primarily as a neurological disorder, it is in fact a multisystem syndrome involving many co-occurring conditions, some primary and some secondary, and they are associated with a considerable burden on patients and their families.

Language in young females with fragile X syndrome: Influence on the neurocognitive profile and adaptive behavior

Fragile X syndrome (FXS) is the leading cause of inherited intellectual disability. The objective of this research is to analyze the relationship between linguistic functions and performance of the following neuropsychological functions: executive, quantitative reasoning, social perception, behavior, social skills, and adaptive behavior. A neuropsychological and behavioral evaluations were carried out with a group of 26 girls with FXS, and 14 girls without FXS as a control group, using standardized tests. The two groups were homogeneous in age and IQ. Significant differences were found between groups in the relationship between some language processes: inhibition, auditory working memory, cognitive flexibility, level of social adaptation, self-direction, conceptual adaptation, academic skills, leadership ability, theory of mind, and arithmetic. In the group of girls with FXS, it was found that different aspects of language influence some of the executive functions evaluated, in addition to some specific aspects of social perception, adaptive behavior, and quantitative reasoning, in different ways. Future research should incorporate the study of the influence of other cognitive variables such as visual perception and executive function on behavioral, social, and adaptive aspects to know the real influence of all the cognitive variables on the behavior of girls with FXS.

"Just tell me what's going on": The views of parents of children with genetic conditions regarding the research use of their child's electronic health record

OBJECTIVE

The purpose of this study was to understand the ethical, legal, and social issues described by parents of children with known or suspected genetic conditions that cause intellectual and developmental disabilities regarding research use of their child's electronic health record (EHR).

MATERIALS AND METHODS

We conducted 4 focus groups with parents of children with a known (n = 12) or suspected (n = 11) genetic condition, as well as 2 comparison groups with parents who had a child with no known genetic condition (n = 15). Focus group transcripts were coded and analyzed using directed content analysis.

RESULTS

After weighing the risks and benefits, parents of children with known or suspected genetic conditions were willing to share their child's EHR for research studies under certain conditions. Preferences were for studies conducted by universities or nonprofits that might benefit their child or others with the same condition. Parents also valued return of research results.

DISCUSSION

Trust, transparency, altruism, and concerns about privacy emerged as factors that affect parents' willingness to allow research use of their child's EHR.

CONCLUSION

Researchers should consider how to build trust with parents by increasing transparency of the research process and explaining specifically how they will ensure the confidentiality of EHR data.

A missense variant in the nuclear export signal of the FMR1 gene causes intellectual disability

Fragile X syndrome (FXS) is the most common monogenetic cause of intellectual disability and autism spectrum disorders. Mostly, FXS is caused by transcriptional silencing of the FMR1 gene due to a repeat expansion in the 5' UTR, and consequently lack of the protein product FMRP. However, in rare cases FXS is caused by other types of variants in the FMR1 gene. We describe a missense variant in the FMR1 gene, identified through whole-exome sequencing, in a boy with intellectual disability and behavioral problems. The variant is located in the FMRP's nuclear export signal (NES). We performed expression and localization studies of the variant in hair roots and HEK293 cells. Our results show normal expression but significant retention of the FMRP in the cells' nucleus. This finding suggests a possible FMRP reduction at its essential functional sites in the dendrites and the synaptic compartments and possible interference of other cellular processes in the nucleus. Together, this might lead to a FXS phenotype in the boy.

Parent Perspectives on Augmentative and Alternative Communication Integration for Children With Fragile X Syndrome: It Starts in the Home

Many children with fragile X syndrome (FXS) have complex communication needs and may benefit from augmentative and alternative communication (AAC). This qualitative study explored how four mother-child dyads used AAC in the home. Data were collected using participant observations, open-ended interviews, and record reviews, and analyzed using grounded theory methods. Findings revealed that mothers found AAC to be a useful tool for addressing their children's complex communication needs, but practical and personal factors impacted its use in the home. This study sheds light on how mothers of children with FXS view and utilize AAC as a way to promote communication at home. Understanding parental perspectives can help to guide professionals in planning appropriate AAC interventions specific to FXS.

Understanding attention, memory and social biases in fragile X syndrome: Going below the surface with a multi-method approach

Fragile X syndrome (FXS) is characterised by atypical social behaviours, such as gaze aversion. However, it remains unclear whether, or if so how, these behaviours affect cognitive processing and influence memory. We asked children with FXS (N = 16) and typically developing children (TD; N = 46) to explore naturalistic scenes containing social and non-social salient items unrelated to their task at hand (searching for a simple target object). We also assessed children's memory for target locations. We complemented behavioural responses with eye-tracking data for the subset of participants who managed to comply with calibration and the demands of the experimental testing session (6 children with FXS and 43 TD children). Children with FXS performed well at the experimental task, and showed similar accuracy and speed in locating targets in natural scenes to children of equivalent verbal abilities. They also learned target locations over blocks, but their memory of target locations was not as precise as that of comparison children. In addition, children with FXS initially directed few first looks to salient social items within the scenes, but these looks increased over blocks. Like TD children, children with FXS also dwelled gaze upon social items while recalling target locations from memory. Individual differences in everyday social characteristics also related to gaze and behavioural measures. In conclusion, experimental approaches can highlight cognitive underpinnings of atypical social behaviour in FXS, pinpointing both similarities and differences to TD individuals.

Factors impacting the transition to adulthood of youth with fragile X syndrome and their families: Facilitators, obstacles and needs

BACKGROUND

The transition from school to adulthood is a critical time for families of youth with disabilities. Few studies have focused on the needs of families of youths with fragile X syndrome. This syndrome is often associated with intellectual disability and autism spectrum disorder, which creates specific needs that must be documented to improve transition planning. The aim of the current study was to document factors impacting transition planning and describe parents' experiences during this period.

METHOD

Individual interviews were conducted with thirteen parents of young people with fragile X syndrome. Two research team members analysed the interviews separately.

RESULTS

Factors related to the youth, the youth's family and the steps taken by the various institutions involved during this period seem to impact this transition and contributed to families' anxiety. A clear, uniform transition planning process, initiated early enough to have time for exploratory work placements, and gradual integration emerged as crucial facilitators for the parents in this study.

CONCLUSIONS

Understanding the reality of people with fragile X syndrome and their families will help to adapt services and develop concrete plans for their future.

Trajectories of Change in the Behavioral and Health Phenotype of Adolescents and Adults with Fragile X Syndrome and Intellectual Disability: Longitudinal Trends Over a Decade

This study examined trajectories of daily living skills, behavior problems, body mass index (BMI), and health conditions spanning nearly a decade in adolescents and adults with fragile X syndrome (N = 134; age range at study end = 19-49 years), examining influences of sex and autism spectrum disorder (ASD) symptoms. Hierarchical linear modeling revealed early increases in daily living skills, with decreases at older ages. Behavior problems became less severe over time, with some increases at older ages. Individuals gained weight and had increasing health problems over time. Fewer ASD symptoms were associated with greater daily living skills and fewer behavior problems at study start. This study offers some of the first prospective quantitative analyses of behavioral and health life course trajectories in FXS.

Fragile X Syndrome-Associated Emergency Department Visits in the United States, 2006-2011

Using national data, we examined emergency department (ED) encounters during 2006-2011 for which a diagnosis code for fragile X syndrome (FXS) was present (n = 7,217). Almost half of ED visits coded for FXS resulted in hospitalization, which is much higher than for ED visits not coded for FXS. ED visits among females coded for FXS were slightly more likely to result in hospitalization. These findings underscore the importance of surveillance systems that could accurately identify individuals with FXS, track healthcare utilization and co-occurring conditions, and monitor quality of care in order to improve care and reduce FXS-associated morbidity.

Supporting informed clinical trial decisions: Results from a randomized controlled trial evaluating a digital decision support tool for those with intellectual disability

Background

Informed consent requires that individuals understand the nature of the study, risks and benefits of participation. Individuals with intellectual disabilities (ID) have cognitive and adaptive impairments that may affect their ability to provide informed consent. New treatments and clinical trials for fragile X syndrome, the most commonly known inherited cause of ID, necessitate the development of methods to improve the informed consent process. The goal of this study was to compare the efficacy of a digital decision support tool with that of standard practice for informed consent and to examine whether the tool can improve decisional capacity for higher functioning individuals.

Methods

Participants (N = 89; mean age = 21.2 years) were allocated to the experimental group (consenting information provided via the digital decision support tool), or the comparison group (information provided via standard practice). Participants were assessed on four aspects of decisional capacity (Understanding, Appreciating, Reasoning, and Expressing a choice). We used regression analyses to test the impact of the tool on each outcome, repeating the analyses on the higher functioning subsample.

Results

No differences existed in any domain of decisional capacity for the sample in full. However, participants in the higher IQ subsample who used the tool scored better on Understanding after adjustment (β = 0.25, p = 0.04), but not on Appreciating or Reasoning. No differences by experimental group existed in the decision to join the hypothetical trial for the full sample or higher functioning subsample.

Conclusions

A decision support tool shows promise for individuals with fragile X syndrome with higher cognitive abilities. Future studies should examine the level of cognitive ability needed for sufficient understanding, whether these findings can be translated to other clinical populations, and the impact of the tool in larger trials and on trial retention.

Educational Case: Fragile X Syndrome with Size Mosaicism

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, seehttp://journals.sagepub.com/doi/10.1177/2374289517715040.

Identifying Atypical Development: A Role of Day-Care Workers?

Identifying the early signs of developmental disability is important for ensuring timely diagnosis and early intervention. Day-care workers may be in a prime position to notice potential developmental deviations, but it is unclear if they can accurately recognize subtle early signs of atypical development. Sixty day-care workers examined home-videos of very young children with fragile X syndrome and typically developing children. Results indicated that most day-care workers can distinguish typical and atypical development in general and might therefore have an important role in early identification. Special work experience and advanced pedagogical training appeared to boost day-care workers' sensitivity to detect atypical features in early development and to provide effective daily surveillance.

A Description of the Educational Setting Among Individuals With Fragile X Syndrome

Children with fragile X syndrome (FXS) display wide-ranging intellectual and behavioral abilities that affect daily life. We describe the educational setting of students with FXS and assess the relationships between school setting, co-occurring conditions, and functional ability using a national survey sample ( n = 982). The majority of students with FXS in this sample have formal individualized education plans, spend part of the day outside regular classrooms, and receive modifications when in a regular classroom. Males with FXS and certain co-occurring conditions (autism, aggression, and self-injurious behavior) are more likely to spend the entire day outside regular classrooms, compared to males without these co-occurring conditions. Students who spend more time in regular classrooms are more likely to perform functional tasks without help.

Clinical Development of Targeted Fragile X Syndrome Treatments: An Industry Perspective

Fragile X syndrome (FXS) is the leading known cause of inherited intellectual disability and autism spectrum disorder. It is caused by a mutation of the fragile X mental retardation 1 (FMR1) gene, resulting in a deficit of fragile X mental retardation protein (FMRP). The clinical presentation of FXS is variable, and is typically associated with developmental delays, intellectual disability, a wide range of behavioral issues, and certain identifying physical features. Over the past 25 years, researchers have worked to understand the complex relationship between FMRP deficiency and the symptoms of FXS and, in the process, have identified several potential targeted therapeutics, some of which have been tested in clinical trials. Whereas most of the basic research to date has been led by experts at academic institutions, the pharmaceutical industry is becoming increasingly involved with not only the scientific community, but also with patient advocacy organizations, as more promising pharmacological agents are moving into the clinical stages of development. The objective of this review is to provide an industry perspective on the ongoing development of mechanism-based treatments for FXS, including identification of challenges and recommendations for future clinical trials.

A Digital Health App to Assess Decisional Capacity to Provide Informed Consent: Protocol for a Randomized Controlled Trial

Background

Any study with human subjects must have a robust consent process to ensure that participants understand the study and can decide whether they want to be involved. Investigators must determine whether a potential study participant is able to make an informed decision and what modifications or supports are needed to maximize participation in decision making. A variety of approaches have been used to modify consent forms and the consent process to increase the research participants’ decisional capacity. This protocol describes a randomized controlled trial (RCT) of a digital health app to support decision making among individuals contemplating providing consent to participate in a clinical trial.

Objective

The objective of this RCT will be to determine if the use of a tablet-based app facilitates greater participation in and satisfaction with the consent process compared with standard practice and identify which individual factors are associated with better response to the decision aid. We hypothesize that the tablet-based version of the consent process will promote more informed decision making, including decisions that are more consistent with individual preferences and values expressed during qualitative data collection.

Methods

A two-arm RCT will be conducted in a sample of approximately 100 individuals with fragile X syndrome in their homes across the United States.

Results

Data analysis will be completed by late 2018.

Conclusions

By developing and testing a novel consent decision aid, we will have a better understanding of whether and how technological support can optimize the fit between the decisional capacity and the decisional process.

Trial Registration

ClinicalTrials.gov NCT02465931; https://clinicaltrials.gov/ct2/show/NCT02465931 (Archived by WebCite at http://www.webcitation.org/72Q3xJQAw)

International Registered Report Identifier (IRRID)

PRR1-10.2196/10360

Mavoglurant in Fragile X Syndrome: Results of two open-label, extension trials in adults and adolescents

Fragile X syndrome (FXS) is the most common monogenic cause of inherited intellectual and developmental disabilities. Mavoglurant, a selective metabotropic glutamate receptor subtype-5 antagonist, has shown positive neuronal and behavioral effects in preclinical studies, but failed to demonstrate any behavioral benefits in two 12-week, randomized, placebo-controlled, double-blind, phase IIb studies in adults and adolescents with FXS. Here we report the long-term safety (primary endpoint) and efficacy (secondary endpoint) results of the open-label extensions. Adolescent (n = 119, aged 12–19 years) and adult (n = 148, aged 18–45 years) participants received up to 100 mg bid mavoglurant for up to 34 months. Both extension studies were terminated prematurely due to lack of proven efficacy in the core studies. Mavoglurant was well tolerated with no new safety signal. Five percent of adults and 16.9 percent of adolescents discontinued treatment due to adverse events. Gradual and consistent behavioral improvements as measured by the ABC-C_FX scale were observed, which were numerically superior to those seen in the placebo arm of the core studies. These two extension studies confirm the long-term safety of mavoglurant in FXS, but further investigations are required to determine whether and under which conditions the significant preclinical results obtained with mGluR5 inhibition can translate to humans.

Developmental trajectories of executive functions in young males with fragile X syndrome

BACKGROUND

Executive functions (EF) have been identified as impaired in FXS, but few studies have examined their developmental trajectories.

AIMS

The primary aim of this longitudinal study was to examine the development of EF in young males with FXS compared to Mental Age (MA)-matched controls.

METHODS AND PROCEDURES

The sample comprised 56 boys with FXS (ages 7-13 years), and 48 MA-matched typical boys (ages 4-8 years). EF tasks included measures of inhibitory control, working memory, cognitive flexibility/set-shifting, problem solving/planning, and processing speed. Tasks were administered at three time points over five-years.

OUTCOMES AND RESULTS

The MA-Matched Typical boys significantly outperformed the FXS boys on all EF tasks, with the FXS Group showing a pattern of slow, but positive growth on most EF tasks. For working memory tasks, significant interactions were noted between MA and autism symptom severity, and MA and medication status. The probability of task completion increased with higher MA.

CONCLUSIONS AND IMPLICATIONS

These findings contribute to our understanding of the development of EF in this population. They also lay the foundation for use of EF tasks in treatment efforts, particularly with respect to documenting improvements and practice effects, and in understanding associations with targeted developmental outcomes.

A comparison of functional academic and daily living skills in males with fragile X syndrome with and without autism

BACKGROUND

Adaptive behaviors, such as functional academic and daily living skills, are critical for independence in adults with intellectual and developmental disabilities. However, little is known about these skills in fragile X syndrome (FXS), the most common form of inherited intellectual disability.

AIMS

The purposes of this study were to describe the functional academic and daily living skills of males diagnosed with FXS across different age groups and compare skill attainment by autism status and other common co-occurring conditions.

METHODS AND PROCEDURES

We used survey methods to assess parent-reported functional academic and daily living skills in 534 males with FXS. Functional academic skills included time and schedules, money, math, reading, and writing skills. Daily living skills included hygiene, cooking, laundry and housekeeping, transportation, and safety skills.

OUTCOMES AND RESULTS

Analyses examined functional academic and daily living skills in a cross-sectional sample of males between ages 5 and 67. Differences in skill attainment were found by child age, co-morbid autism status, total number of co-occurring conditions, and respondent education. Functional academic and daily living skills were predictive of community employment and independent living.

CONCLUSIONS AND IMPLICATIONS

These data provide important information on the mastery of both foundational and more complex adaptive skills in males with FXS. Both functional academic and daily living skills were predictive of measures of independence above and beyond other child and family characteristics. These findings point to the need to focus interventions to support the attainment of independence in males with FXS.

Nanoparticle delivery of CRISPR into the brain rescues a mouse model of fragile X syndrome from exaggerated repetitive behaviours

Technologies that can safely edit genes in the brains of adult animals may revolutionize the treatment of neurological diseases and the understanding of brain function. Here, we demonstrate that intracranial injection of CRISPR-Gold, a nonviral delivery vehicle for the CRISPR-Cas9 ribonucleoprotein, can edit genes in the brains of adult mice in multiple mouse models. CRISPR-Gold can deliver both Cas9 and Cpf1 ribonucleoproteins, and can edit all of the major cell types in the brain, including neurons, astrocytes and microglia, with undetectable levels of toxicity at the doses used. We also show that CRISPR-Gold designed to target the metabotropic glutamate receptor 5 (mGluR5) gene can efficiently reduce local mGluR5 levels in the striatum after an intracranial injection. The effect can also rescue mice from the exaggerated repetitive behaviours caused by fragile X syndrome, a common single-gene form of autism spectrum disorders. CRISPR-Gold may significantly accelerate the development of brain-targeted therapeutics and enable the rapid development of focal brain-knockout animal models.

A Digital Decision Support Tool to Enhance Decisional Capacity for Clinical Trial Consent: Design and Development

BACKGROUND

Challenges in the clinical and research consent process indicate the need to develop tailored, supportive interventions for all individuals, especially those with limited decisional capacity. We developed a tool to enhance shared decision making and the decisional capacity for individuals with fragile X syndrome engaged in the informed consent process for a clinical trial.

OBJECTIVE

We describe the design and development process of a tablet-based decision support tool.

METHODS

Our development process for the decision support tool employed a user-centered, feature-driven design approach. We began with an environmental scan to catalog relevant mobile apps, and we conducted interviews with people with a diagnosis of fragile X syndrome and clinicians at fragile X syndrome clinics. To develop content for the decision support tool, we extracted key concepts and elements from a real clinical trial consent form and rewrote it using plain-language principles.

RESULTS

We used iterative testing to continuously evaluate and revise the decision support tool content. The tool was finalized in 2016 and contained a series of vignettes, quiz questions, and a sorting activity. A randomized controlled trial was then conducted to compare the efficacy of the decision support tool with a standard verbal presentation of material that mimicked typical informed consent practice.

CONCLUSIONS

The informed consent process is primed to leverage digital health resources that promote increased understanding and engagement of research participants in the consent and research process. The process and experiences we describe may provide a model for other digital health design and development initiatives seeking to create more interactive and accessible decision support resources.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02465931; https://www.clinicaltrials.gov/ct2/show/NCT02465931 (Archived by WebCite at http://www.webcitation.org/6zx2KY9YW).

De novo sequencing and initial annotation of the Mongolian gerbil (Meriones unguiculatus) genome

The Mongolian gerbil (Meriones unguiculatus) is a member of the rodent family that displays several features not found in mice or rats, including sensory specializations and social patterns more similar to those in humans. These features have made gerbils a valuable animal for research studies of auditory and visual processing, brain development, learning and memory, and neurological disorders. Here, we report the whole gerbil annotated genome sequence, and identify important similarities and differences to the human and mouse genomes. We further analyze the chromosomal structure of eight genes with high relevance for controlling neural signaling and demonstrate a high degree of homology between these genes in mouse and gerbil. This homology increases the likelihood that individual genes can be rapidly identified in gerbil and used for genetic manipulations. The availability of the gerbil genome provides a foundation for advancing our knowledge towards understanding evolution, behavior and neural function in mammals. ACCESSION NUMBER: The Whole Genome Shotgun sequence data from this project has been deposited at DDBJ/ENA/GenBank under the accession NHTI00000000. The version described in this paper is version NHTI01000000. The fragment reads, and mate pair reads have been deposited in the Sequence Read Archive under BioSample accession SAMN06897401.

Fragile X syndrome and fragile X-associated disorders

Fragile X syndrome (FXS) is caused by a full mutation on the FMR1 gene and a subsequent lack of FMRP, the protein product of FMR1. FMRP plays a key role in regulating the translation of many proteins involved in maintaining neuronal synaptic connections; its deficiency may result in a range of intellectual disabilities, social deficits, psychiatric problems, and dysmorphic physical features. A range of clinical involvement is also associated with the FMR1 premutation, including fragile X-associated tremor ataxia syndrome, fragile X-associated primary ovarian insufficiency, psychiatric problems, hypertension, migraines, and autoimmune problems. Over the past few years, there have been a number of advances in our knowledge of FXS and fragile X-associated disorders, and each of these advances offers significant clinical implications. Among these developments are a better understanding of the clinical impact of the phenomenon known as mosaicism, the revelation that various types of mutations can cause FXS, and improvements in treatment for FXS.

Assessing the Fragile X Syndrome Newborn Screening Landscape

BACKGROUND

Fragile X syndrome (FXS) is the most common known inherited form of intellectual disability. Early identification is an important step in linking FXS individuals with appropriate and timely medical and social services. Newborn screening (NBS) is 1 approach that has been used for other conditions to facilitate early identification.

METHODS

A literature review was conducted to identify issues, barriers, challenges, and approaches to addressing challenges related to NBS for FXS. Search terms included: fragile X syndrome, FMR1, newborn screening, screening, and genetic testing. To supplement the literature review, 9 key informant interviews were conducted. Information gathered through these interviews supplemented what was identified in the literature. Information from both the literature review and supplemental interviews was reviewed by 3 researchers who discussed and came to consensus on thematic areas and categorization of issues.

RESULTS

The barriers and challenges related to NBS for FXS identified in the literature and by experts and stakeholders are categorized into 5 thematic areas: public health burden, treatment, timing, screening/testing methodologies, and translating results. Summaries of these issues and barriers are provided, along with potential approaches to addressing them.

CONCLUSIONS

The issues and barriers described in this article highlight limited areas of knowledge that need be addressed to improve our understanding of FXS and the potential benefit of NBS. The landscape of NBS for FXS could be influenced by a series of research findings over time or a larger breakthrough that demonstrates an effective targeted treatment that has to be implemented early in life.