RESUMEN
Autism spectrum disorder (ASD) is often grouped with other brain-related phenotypes into a broader category of neurodevelopmental disorders (NDDs). In clinical practice, providers need to decide which genes to test in individuals with ASD phenotypes, which requires an understanding of the level of evidence for individual NDD genes that supports an association with ASD. Consensus is currently lacking about which NDD genes have sufficient evidence to support a relationship to ASD. Estimates of the number of genes relevant to ASD differ greatly among research groups and clinical sequencing panels, varying from a few to several hundred. This Roadmap discusses important considerations necessary to provide an evidence-based framework for the curation of NDD genes based on the level of information supporting a clinically relevant relationship between a given gene and ASD.
Asunto(s)
Trastorno del Espectro Autista/genética , Medicina Basada en la Evidencia/métodos , Estudios de Asociación Genética/métodos , Encéfalo/crecimiento & desarrollo , Cognición/fisiología , Humanos , Discapacidad Intelectual/genéticaRESUMEN
Duchenne muscular dystrophy (DMD) is characterized by loss of dystrophin in muscle, however patients also have variable degree of intellectual disability and neurobehavioural co-morbidities. In contrast to muscle, in which a single full-length dystrophin isoform (Dp427) is produced, multiple isoforms are produced in the brain, and their deficiency accounts for the variability of CNS manifestations, with increased risk of comorbidities in patients carrying mutations affecting the 3' end of the gene, which disrupt expression of shorter Dp140 and Dp71 isoforms. A mouse model (mdx mouse) lacks Dp427 in muscle and CNS and exhibits exaggerated startle responses to threat, linked to the deficiency of dystrophin in limbic structures such as the amygdala, which normalize with postnatal brain dystrophin-restoration therapies. A pathological startle response is not a recognized feature of DMD, and its characterization has implications for improved clinical management and translational research. To investigate startle responses in DMD, we used a novel fear-conditioning task in an observational study of 56 males aged 7-12 years (31 affected boys, mean age 9.7 ± 1.8 years; 25 controls, mean age 9.6 ± 1.4 years). Trials of two neutral visual stimuli were presented to participants: one 'safe' cue presented alone; one 'threat' cue paired with an aversive noise to enable conditioning of physiological startle responses (skin conductance response and heart rate). Retention of conditioned physiological responses was subsequently tested by presenting both cues without the aversive noise in an 'Extinction' phase. Primary outcomes were the initial unconditioned skin conductance and change in heart rate responses to the aversive 'threat' and acquisition and retention of conditioned responses after conditioning. Secondary and exploratory outcomes were neuropsychological measures and genotype associations. The mean unconditioned skin conductance response was greater in the DMD group than controls [mean difference 3.0 µS (1.0, 5.1); P = 0.004], associated with a significant threat-induced bradycardia only in the patient group [mean difference -8.7 bpm (-16.9, -0.51); P = 0.04]. Participants with DMD found the task more aversive than controls, with increased early termination rates during the Extinction phase (26% of DMD group versus 0% of controls; P = 0.007). This study provides the first evidence that boys with DMD show similar increased unconditioned startle responses to threat to the mdx mouse, which in the mouse respond to brain dystrophin restoration. Our study provides new insights into the neurobiology underlying the complex neuropsychiatric co-morbidities in DMD and defines an objective measure of this CNS phenotype, which will be valuable for future CNS-targeted dystrophin-restoration studies.
Asunto(s)
Distrofina , Distrofia Muscular de Duchenne , Masculino , Ratones , Animales , Distrofina/genética , Distrofina/metabolismo , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/patología , Reflejo de Sobresalto , Ratones Endogámicos mdx , Encéfalo/patología , Biomarcadores/metabolismo , Isoformas de Proteínas/metabolismoRESUMEN
BACKGROUND: Some people with eating disorders have difficulties with social communication. However, no longitudinal evidence regarding the direction of this association exists. We investigated trajectories of autistic social traits across childhood and adolescence in adolescents with and without disordered eating behaviours in early adolescence. METHODS: We used data from the Avon Longitudinal Study of Parents and Children. Our disordered eating measure indicated presence of any, monthly and weekly disordered eating (fasting, purging, dieting, binge eating) at age 14 years. Autistic social traits were reported by mothers using the Social and Communication Disorders Checklist (SCDC) at age seven, 11, 14 and 16 years. We modelled SCDC score trajectories using multilevel negative binomial models adjusting for a number of child- and maternal-level confounders. RESULTS: Of the 5,381 adolescents included in our sample, 421 (7.8%) experienced one or more disordered eating behaviours, and 148 (2.8%) weekly episodes. Adolescents with disordered eating had a 20% increase in SCDC scores (relative risk (RR) 1.23, 95% confidence interval (CI):1.14, 1.32) compared to those without disordered eating. This association was particularly apparent for those reporting weekly (RR 1.43, 95%CI: 1.27, 1.61) as opposed to monthly disordered eating (RR 1.12, 95%CI: 1.01, 1.22). CONCLUSIONS: Greater autistic social traits in childhood could represent a risk factor for the development of disordered eating in adolescence. Although mechanisms of this association need to be elucidated, clinicians should be aware that autistic social traits could have predated the eating disorder when managing people with these conditions.
Asunto(s)
Trastorno Autístico , Trastornos de Alimentación y de la Ingestión de Alimentos , Adolescente , Trastorno Autístico/epidemiología , Estudios de Cohortes , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Femenino , Humanos , Recién Nacido , Estudios Longitudinales , Factores de Riesgo , Factores Sociológicos , Reino Unido/epidemiologíaRESUMEN
BACKGROUND: Turner Syndrome (TS; 45,X) is a sex chromosome aneuploidy associated with deficits in social interaction, for which clinical care guidelines have recently recommended trialling a social skills training intervention. The present study aimed to gather preliminary evidence to support a training programme for young women. METHODS: Semi-structured interviews and psychometric questionnaires about social ability were administered to young women with TS aged 16 to 25 years old (n=17) and their parents (n=20). Interview transcripts were analysed using thematic analysis. RESULTS: Although young women with TS experienced a "wide range of social competencies," they attributed social challenges to "personal and contextual factors." The magnitude of these challenges to social integration intensified during adolescence. They felt increasingly "out of sync" with their peers. They also considered their social abilities to be better than their parents did; on a scale of autistic traits (rated by parents), half had mild to severe autistic traits. Most expressed interest in taking part in a social skills programme. CONCLUSION: Young women with TS are aware they experience difficulties in social communication, and they express interest in improving their social skills. Accordingly, social skills training during adolescence would be welcomed by them and their families. Any intervention should take account of their feelings of social dislocation arising from hearing difficulties together with limited recognition, and slow processing, of social cues.
Asunto(s)
Interacción Social , Habilidades Sociales , Síndrome de Turner/psicología , Adolescente , Adulto , Factores de Edad , Emociones , Femenino , Humanos , Padres/psicología , Investigación Cualitativa , Ajuste Social , Adulto JovenRESUMEN
Autism spectrum disorder (ASD) is characterized by impairments in social cognition, a function associated with the amygdala. Subdivisions of the amygdala have been identified which show specificity of structure, connectivity, and function. Little is known about amygdala connectivity in ASD. The aim of this study was to investigate the microstructural properties of amygdala-cortical connections and their association with ASD behaviours, and whether connectivity of specific amygdala subregions is associated with particular ASD traits. The brains of 51 high-functioning young adults (25 with ASD; 26 controls) were scanned using MRI. Amygdala volume was measured, and amygdala-cortical connectivity estimated using probabilistic tractography. An iterative 'winner takes all' algorithm was used to parcellate the amygdala based on its primary cortical connections. Measures of amygdala connectivity were correlated with clinical scores. In comparison with controls, amygdala volume was greater in ASD (F(1,94) = 4.19; p = .04). In white matter (WM) tracts connecting the right amygdala to the right cortex, ASD subjects showed increased mean diffusivity (t = 2.35; p = .05), which correlated with the severity of emotion recognition deficits (rho = -0.53; p = .01). Following amygdala parcellation, in ASD subjects reduced fractional anisotropy in WM connecting the left amygdala to the temporal cortex was associated with with greater attention switching impairment (rho = -0.61; p = .02). This study demonstrates that both amygdala volume and the microstructure of connections between the amygdala and the cortex are altered in ASD. Findings indicate that the microstructure of right amygdala WM tracts are associated with overall ASD severity, but that investigation of amygdala subregions can identify more specific associations.
Asunto(s)
Amígdala del Cerebelo/diagnóstico por imagen , Trastorno del Espectro Autista/diagnóstico por imagen , Adolescente , Adulto , Amígdala del Cerebelo/patología , Trastorno del Espectro Autista/patología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Imagen de Difusión Tensora , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/patología , Tamaño de los Órganos , Índice de Severidad de la Enfermedad , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Adulto JovenRESUMEN
BACKGROUND: Autism is a dimensional condition, representing the extreme end of a continuum of social competence that extends throughout the general population. Currently, little is known about how autistic social traits (ASTs), measured across the full spectrum of severity, develop during childhood and adolescence, including whether there are developmental differences between boys and girls. Therefore, we sought to chart the trajectories of ASTs in the general population across childhood and adolescence, with a focus on gender differences. METHODS: Participants were 9,744 males (n = 4,784) and females (n = 4,960) from ALSPAC, a UK birth cohort study. ASTs were assessed when participants were aged 7, 10, 13 and 16 years, using the parent-report Social Communication Disorders Checklist. Data were modelled using latent growth curve analysis. RESULTS: Developmental trajectories of males and females were nonlinear, showing a decline from 7 to 10 years, followed by an increase between 10 and 16 years. At 7 years, males had higher levels of ASTs than females (mean raw score difference = 0.88, 95% CI [.72, 1.04]), and were more likely (odds ratio [OR] = 1.99; 95% CI, 1.82, 2.16) to score in the clinical range on the SCDC. By 16 years this gender difference had disappeared: males and females had, on average, similar levels of ASTs (mean difference = 0.00, 95% CI [-0.19, 0.19]) and were equally likely to score in the SCDC's clinical range (OR = 0.91, 95% CI, 0.73, 1.10). This was the result of an increase in females' ASTs between 10 and 16 years. CONCLUSIONS: There are gender-specific trajectories of autistic social impairment, with females more likely than males to experience an escalation of ASTs during early- and midadolescence. It remains to be discovered whether the observed female adolescent increase in ASTs represents the genuine late onset of social difficulties or earlier, subtle, pre-existing difficulties becoming more obvious.
Asunto(s)
Trastorno del Espectro Autista/psicología , Desarrollo Infantil , Factores Sociológicos , Adolescente , Factores de Edad , Niño , Femenino , Humanos , Masculino , Factores Sexuales , Conducta Social , Trastorno de Comunicación Social/psicologíaRESUMEN
Recurrent deletions and duplications at the 2q13 locus have been associated with developmental delay (DD) and dysmorphisms. We aimed to undertake detailed clinical characterization of individuals with 2q13 copy number variations (CNVs), with a focus on behavioral and psychiatric phenotypes. Participants were recruited via the Unique chromosomal disorder support group, U.K. National Health Service Regional Genetics Centres, and the DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources (DECIPHER) database. A review of published 2q13 patient case reports was undertaken to enable combined phenotypic analysis. We present a new case series of 2q13 CNV carriers (21 deletion, 4 duplication) and the largest ever combined analysis with data from published studies, making a total of 54 deletion and 23 duplication carriers. DD/intellectual disabilities was identified in the majority of carriers (79% deletion, 70% duplication), although in the new cases 52% had an IQ in the borderline or normal range. Despite the median age of the new cases being only 9 years, 64% had a clinical psychiatric diagnosis. Combined analysis found attention deficit hyperactivity disorder (ADHD) to be the most frequent diagnosis (48% deletion, 60% duplication), followed by autism spectrum disorders (33% deletion, 17% duplication). Aggressive (33%) and self-injurious behaviors (33%) were also identified in the new cases. CNVs at 2q13 are typically associated with DD with mildly impaired intelligence, and a high rate of childhood psychiatric diagnoses-particularly ADHD. We have further characterized the clinical phenotype related to imbalances of the 2q13 region and identified it as a region of interest for the neurobiological investigation of ADHD.
Asunto(s)
Cromosomas Humanos Par 2/genética , Discapacidades del Desarrollo/genética , Trastornos Mentales/genética , Adolescente , Adulto , Niño , Preescolar , Aberraciones Cromosómicas , Deleción Cromosómica , Duplicación Cromosómica , Variaciones en el Número de Copia de ADN/genética , Femenino , Duplicación de Gen/genética , Humanos , Discapacidad Intelectual/genética , Masculino , Fenotipo , Reino UnidoRESUMEN
The X chromosome has played a critical role in the development of sexually selected characteristics for over 300 million years, and during that time it has accumulated a disproportionate number of genes concerned with mental functions. There are relatively specific effects of X-linked genes on social cognition, language, emotional regulation, visuospatial, and numerical skills. Many human X-linked genes outside the X-Y pairing pseudoautosomal regions escape X-inactivation. Dosage differences in the expression of such genes (which constitute at least 15% of the total) are likely to play an important role in male-female neural differentiation, and in cognitive deficits and behavioral characteristics, particularly in the realm of social communication, that are associated with sex chromosome aneuploidies. © 2016 Wiley Periodicals, Inc.
Asunto(s)
Aneuploidia , Encéfalo/fisiología , Cognición/fisiología , Caracteres Sexuales , Cromosomas Sexuales/genética , Conducta Social , Animales , Encéfalo/patología , Humanos , Trastornos Mentales/genética , Trastornos Mentales/patología , Trastornos Mentales/fisiopatología , Diferenciación Sexual/genéticaRESUMEN
BACKGROUND: Social (pragmatic) communication disorder (SPCD) is a new diagnosis introduced by DSM-5, characterised by problems with verbal and nonverbal social communication. It is currently unclear whether SPCD is a valid diagnostic category, because little is known about the characteristics of those who meet its criteria. We sought to identify and describe cases of SPCD, to contribute to debates about its validity. We investigated whether the symptoms of SPCD cluster together to form a coherent syndrome that is distinct from autism spectrum disorder (ASD) in terms of its core and associated features. METHODS: Participants were young people (N = 1,081, age range = 4-18 years) who had attended a specialist social communication disorders clinic for children with fluent language and normal-range intelligence. Standardised parent-report data were collected using the Developmental, Dimensional and Diagnostic Interview (3Di), Child Communication Checklist (CCC) and Strengths and Difficulties Questionnaire (SDQ). An algorithm was designed using 3Di and CCC items to implement DSM-5 SPCD criteria. RESULTS: Eighty-eight young people met our criteria for SPCD, with 801 meeting DSM-5 ASD criteria and the remaining 192 having neither SPCD nor ASD ('clinical comparison group'). The core symptoms of SPCD co-occurred to a moderate degree (average interitem correlation = .22). SPCD cases had autistic social difficulties that were intermediate between ASD and the clinical comparison group. SPCD was associated with high rates of nonautistic psychopathology, with 63.5% scoring in the abnormal range of the SDQ's Total Problems scale. CONCLUSIONS: We did not find evidence that SPCD is qualitatively distinct from ASD. Rather, it appears to lie on the borderlands of the autism spectrum, describing those with autistic traits that fall just below the threshold for an ASD diagnosis. SPCD may have clinical utility for identifying people with autistic traits that are insufficiently severe for ASD diagnosis, but who nevertheless require support.
Asunto(s)
Trastorno del Espectro Autista/diagnóstico , Trastorno de Comunicación Social/diagnóstico , Adolescente , Trastorno del Espectro Autista/fisiopatología , Niño , Preescolar , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Trastorno de Comunicación Social/fisiopatologíaRESUMEN
The neuropeptides oxytocin and vasopressin are evolutionarily conserved regulators of social perception and behavior. Evidence is building that they are critically involved in the development of social recognition skills within rodent species, primates, and humans. We investigated whether common polymorphisms in the genes encoding the oxytocin and vasopressin 1a receptors influence social memory for faces. Our sample comprised 198 families, from the United Kingdom and Finland, in whom a single child had been diagnosed with high-functioning autism. Previous research has shown that impaired social perception, characteristic of autism, extends to the first-degree relatives of autistic individuals, implying heritable risk. Assessments of face recognition memory, discrimination of facial emotions, and direction of gaze detection were standardized for age (7-60 y) and sex. A common SNP in the oxytocin receptor (rs237887) was strongly associated with recognition memory in combined probands, parents, and siblings after correction for multiple comparisons. Homozygotes for the ancestral A allele had impairments in the range -0.6 to -1.15 SD scores, irrespective of their diagnostic status. Our findings imply that a critical role for the oxytocin system in social recognition has been conserved across perceptual boundaries through evolution, from olfaction in rodents to visual memory in humans.
Asunto(s)
Estudios de Asociación Genética , Polimorfismo de Nucleótido Simple/genética , Receptores de Oxitocina/genética , Reconocimiento en Psicología , Conducta Social , Adolescente , Adulto , Alelos , Niño , Trastornos Generalizados del Desarrollo Infantil/diagnóstico , Trastornos Generalizados del Desarrollo Infantil/genética , Preescolar , Cognición , Endofenotipos , Femenino , Fijación Ocular/genética , Sitios Genéticos/genética , Predisposición Genética a la Enfermedad , Humanos , Masculino , Memoria , Persona de Mediana Edad , Receptores de Vasopresinas/genética , Adulto JovenRESUMEN
AIM: Duchenne muscular dystrophy (DMD) is associated with neuropsychiatric disorders. The aim of the study was to characterize the DMD neuropsychiatric profile fully and to explore underlying genotype/phenotype associations. METHOD: One hundred and thirty males with DMD (mean age 9y 10mo, range 5-17y) in four European centres were included and completed IQ assessment and a neurodevelopmental-screening questionnaire. Of these, 87 underwent comprehensive neuropsychiatric assessment using structured diagnostic interview and parent-reported questionnaires. RESULTS: The overall mean score on the neurodevelopmental questionnaire was significantly abnormal compared with the general population of children (p<0.001). On average, intelligence was below the population mean, with intellectual disability observed in 34 males (26%). Autistic spectrum disorder was identified in 18 (21%), hyperactivity in 21 (24%), and inattention in 38 (44%). Clinical levels of internalizing and externalizing problems were observed in 21 (24%) and 13 (15%) respectively. Over a third of males scored more than two measures of emotional, behavioural, or neurodevelopmental problems. Males with mutations at the 3' end of the DMD gene affecting all protein isoforms had higher rates of intellectual disability and clusters of symptoms. INTERPRETATION: Males with DMD are at very high risk of neuropsychiatric disturbance, and this risk appears to increase with mutations at the 3' end of the gene. Patterns of symptom clusters suggest a DMD neuropsychiatric syndrome, which may require prompt evaluation and early intervention.
Asunto(s)
Déficit de la Atención y Trastornos de Conducta Disruptiva , Trastorno del Espectro Autista , Distrofina/genética , Discapacidad Intelectual , Distrofia Muscular de Duchenne , Problema de Conducta , Adolescente , Déficit de la Atención y Trastornos de Conducta Disruptiva/etiología , Déficit de la Atención y Trastornos de Conducta Disruptiva/genética , Déficit de la Atención y Trastornos de Conducta Disruptiva/fisiopatología , Trastorno del Espectro Autista/etiología , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/fisiopatología , Niño , Preescolar , Humanos , Discapacidad Intelectual/etiología , Discapacidad Intelectual/genética , Discapacidad Intelectual/fisiopatología , Masculino , Distrofia Muscular de Duchenne/complicaciones , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/fisiopatologíaRESUMEN
BACKGROUND: Psychoeducation is an essential component of postdiagnostic care for people with ASD (autism spectrum disorder), but there is currently no evidence base for clinical practice. We designed, manualised and evaluated PEGASUS (psychoeducation group for autism spectrum understanding and support), a group psychoeducational programme aiming to enhance the self-awareness of young people with ASD by teaching them about their diagnosis. METHODS: This single-blind RCT (randomised control trial) involved 48 young people (9-14 years) with high-functioning ASD. Half were randomly assigned to PEGASUS, administered in six weekly group sessions, with the others receiving no additional intervention. ASD-related self-awareness, the primary outcome, was evaluated using the bespoke Autism Knowledge Quiz (AKQ). Secondary outcome measures included the Rosenberg Self-Esteem Scale. All measures were collected during home visits and scored by researchers blind to group assignment. The trial is registered on ClinicalTrials (NCT01187940, http://www.clinicaltrials.gov) and was funded by the Baily Thomas Charitable Trust. RESULTS: Bootstrap multiple regression showed ASD knowledge (ß = .29, p < .001, 95% CIs [0.13, 0.44]) and ASD self-awareness (ß = .42, p = .001, 95% CIs [0.17, 0.67]), measured by number of ASD-related personal strengths and difficulties listed by participants, increased for those who attended PEGASUS (n = 24) compared with controls (n = 24). There was no effect of PEGASUS on self-esteem by self-report (ß = .10, p = .404, 95% CIs [-0.14, 0.35]) or parent report (ß = .12, p = .324, 95% CIs [-0.12, 0.36]). CONCLUSIONS: After PEGASUS, participants had more general knowledge about ASD, and showed a greater awareness of their collection of unique strengths and difficulties associated with ASD. Psychoeducation did not lower self-esteem. This RCT provides initial evidence for PEGASUS's efficacy as a psychoeducation programme for people with ASD.
Asunto(s)
Trastorno del Espectro Autista/rehabilitación , Educación del Paciente como Asunto/métodos , Psicoterapia de Grupo/métodos , Autoevaluación (Psicología) , Adolescente , Niño , Femenino , Humanos , Masculino , Resultado del TratamientoRESUMEN
Autism spectrum disorders (ASD) are a heterogeneous group of neurodevelopmental disorders with a complex inheritance pattern. While many rare variants in synaptic proteins have been identified in patients with ASD, little is known about their effects at the synapse and their interactions with other genetic variations. Here, following the discovery of two de novo SHANK2 deletions by the Autism Genome Project, we identified a novel 421 kb de novo SHANK2 deletion in a patient with autism. We then sequenced SHANK2 in 455 patients with ASD and 431 controls and integrated these results with those reported by Berkel et al. 2010 (nâ=â396 patients and nâ=â659 controls). We observed a significant enrichment of variants affecting conserved amino acids in 29 of 851 (3.4%) patients and in 16 of 1,090 (1.5%) controls (Pâ=â0.004, ORâ=â2.37, 95% CIâ=â1.23-4.70). In neuronal cell cultures, the variants identified in patients were associated with a reduced synaptic density at dendrites compared to the variants only detected in controls (Pâ=â0.0013). Interestingly, the three patients with de novo SHANK2 deletions also carried inherited CNVs at 15q11-q13 previously associated with neuropsychiatric disorders. In two cases, the nicotinic receptor CHRNA7 was duplicated and in one case the synaptic translation repressor CYFIP1 was deleted. These results strengthen the role of synaptic gene dysfunction in ASD but also highlight the presence of putative modifier genes, which is in keeping with the "multiple hit model" for ASD. A better knowledge of these genetic interactions will be necessary to understand the complex inheritance pattern of ASD.
Asunto(s)
Trastornos Generalizados del Desarrollo Infantil/genética , Proteínas del Tejido Nervioso/genética , Eliminación de Secuencia/genética , Sinapsis/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adulto , Empalme Alternativo/genética , Línea Celular , Niño , Preescolar , Femenino , Dosificación de Gen/genética , Regulación de la Expresión Génica , Humanos , Masculino , Neuronas/citología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sitios de Empalme de ARN/genética , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Sinapsis/patología , Distribución Tisular , Receptor Nicotínico de Acetilcolina alfa 7RESUMEN
Imprinted genes show differential expression between maternal and paternal alleles as a consequence of epigenetic modification that can result in 'parent-of-origin' effects on phenotypic traits. There is increasing evidence from mouse and human studies that imprinted genes may influence behavior and cognitive functioning. Previous work in girls with Turner syndrome (45,XO) has suggested that there are X-linked parent-of-origin effects on brain development and cognitive functioning, although the interpretation of these data in terms of imprinted gene effects has been questioned. We used a 39,XO mouse model to examine the influence of the parental origin of the X chromosome on cognitive behaviors and expression of X-linked genes in brain. Our findings confirm the existence of X-linked imprinted effects on cognitive processes and identify a new maternally expressed imprinted gene candidate on the X chromosome, Xlr3b, which may be of importance in mediating the behavioral effects.
Asunto(s)
Cognición , Impresión Genómica , Proteínas Nucleares/genética , Cromosoma X , Animales , Femenino , Masculino , RatonesRESUMEN
Microfibrillated cellulose (MFC) is a bio-material produced by disintegrating cellulose fibres into fibrillar components. MFC could offer a sustainable solution to packaging needs since it can form an excellent barrier to oxygen. However, a comprehensive understanding of how MFC characteristics impact barrier properties of MFC films or coatings is required. This article critically reviews how the extent of separation of fibres into fibrils-and any resulting changes to the crystallinity and degree of polymerisation of cellulose-influences gas barrier properties of MFC films or coatings. Findings from publications investigating the barrier performance of MFC prepared through different processes intending to increase the effectiveness of fibrillation are evaluated and compared. The effects of processing conditions or chemical pre-treatments on barrier properties of MFC films or coatings are then discussed. A comparison of reported results showed that morphology and size polydispersity of the cellulose strongly influence the barrier properties of MFC. However, changing the MFC production process to decrease fibril diameter and polydispersity can result in changes to cellulose crystallinity; reduction in fibril length; introduction of bulky functional groups; or increased fibril surface charge: all of which could have a negative impact on the barrier properties of the final films or coatings.
RESUMEN
BACKGROUND: SYNGAP1 variants are associated with varying degrees of intellectual disability (ID), developmental delay (DD), epilepsy, autism, and behavioural difficulties. These features may also be observed in other monogenic conditions. There is a need to systematically compare the characteristics of SYNGAP1 with other monogenic causes of ID and DD to identify features unique to the SYNAGP1 phenotype. We aimed to contrast the neurodevelopmental and behavioural phenotype of children with SYNGAP1-related ID (SYNGAP1-ID) to children with other monogenic conditions and a matched degree of ID. METHODS: Participants were identified from the IMAGINE-ID study, a UK-based, national cohort study of neuropsychiatric risk in children with ID of known genetic origin. Thirteen children with SYNGAP1 variants (age 4-16 years; 85% female) were matched (2:1) with 26 controls with other monogenic causes of ID for chronological and mental age, sex, socio-economic deprivation, adaptive behaviour, and physical health difficulties. Caregivers completed the Development and Wellbeing Assessment (DAWBA) and physical health questionnaires. RESULTS: Our results demonstrate that seizures affected children with SYNGAP1-ID (84.6%) more frequently than the ID-comparison group (7.6%; p = < 0.001). Fine-motor development was disproportionally impaired in SYNGAP1-ID, with 92.3% of children experiencing difficulties compared to 50% of ID-comparisons(p = 0.03). Gross motor and social development did not differ between the two groups. Children with SYNGAP1-ID were more likely to be non-verbal (61.5%) than ID-comparisons (23.1%; p = 0.01). Those children able to speak, spoke their first words at the same age as the ID-comparison group (mean = 3.25 years), yet achieved lower language competency (p = 0.04). Children with SYNGAP1-ID compared to the ID-comparison group were not more likely to meet criteria for autism (SYNGAP1-ID = 46.2%; ID-comparison = 30.7%; p = .35), attention-deficit hyperactivity disorder (15.4%;15.4%; p = 1), generalised anxiety (7.7%;15.4%; p = .49) or oppositional defiant disorder (7.7%;0%; p = .15). CONCLUSION: For the first time, we demonstrate that SYNGAP1-ID is associated with fine motor and language difficulties beyond those experienced by children with other genetic causes of DD and ID. Targeted occupational and speech and language therapies should be incorporated early into SYNGAP1-ID management.
Asunto(s)
Discapacidad Intelectual , Proteínas Activadoras de ras GTPasa , Humanos , Femenino , Proteínas Activadoras de ras GTPasa/genética , Masculino , Niño , Adolescente , Preescolar , Discapacidad Intelectual/genética , Discapacidad Intelectual/etiología , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/etiología , Reino Unido , Trastornos del Neurodesarrollo/genética , Estudios de Cohortes , Fenotipo , Epilepsia/genética , Convulsiones/genéticaRESUMEN
BACKGROUND: Parents of individuals with rare neurodevelopmental conditions and intellectual disabilities (ID) are vulnerable to mental health difficulties, which vary between parents and within parents over time. The underlying cause of a child's condition can influence parents' mental health, via uncertain pathways and within unknown time-windows. RESULTS: We analysed baseline data from the IMAGINE-ID cohort, comprising 2655 parents of children and young people with ID of known genetic origin. First, we conducted a factor analysis of the SDQ Impact scale to isolate specific pathways from genetic aetiology to parents' mental health. This suggested a two-factor structure for the SDQ Impact scale, with a "home & distress" dimension and a "participation" dimension. Second, we tested via structural equation modelling (SEM) whether genetic diagnosis affects Impact and mental health directly, or indirectly via children's characteristics. This analysis identified an indirect pathway linking genetic aetiology to parents' mental health, serially through child characteristics (physical disabilities, emotional and behavioural difficulties) and Impact: home & distress. Third, we conducted moderation analysis to explore the influence of time elapsed since genetic diagnosis. This showed that the serial mediation model was moderated by time since diagnosis, with strongest mediating effects among recently diagnosed cases. CONCLUSIONS: There are multiple steps on the pathway from ID-associated genetic diagnoses to parents' mental health. Pathway links are strongest within 5 years of receiving a genetic diagnosis, highlighting opportunities for better post-diagnostic support. Recognition and enhanced support for children's physical and behavioural needs might reduce impact on family life, ameliorating parents' vulnerabilities to mental health difficulties.
Asunto(s)
Discapacidad Intelectual , Salud Mental , Niño , Humanos , Adolescente , Padres/psicología , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genéticaRESUMEN
A range of rare mutations involving micro-deletion or -duplication of genetic material (copy number variants (CNVs)) have been associated with high neurodevelopmental and psychiatric risk (ND-CNVs). Irritability is frequently observed in childhood neurodevelopmental conditions, yet its aetiology is largely unknown. Genetic variation may play a role, but there is a sparsity of studies investigating the presentation of irritability in young people with ND-CNVs. This study aimed to investigate whether there is a difference in irritability in young people with rare ND-CNVs compared to those without ND-CNVs, and to what extent irritability is associated with psychiatric diagnoses and cognitive ability (IQ). Irritability and broader psychopathology were assessed in 485 young people with ND-CNVs and 164 sibling controls, using the child and adolescent psychiatric assessment. Autism was assessed using the social communication questionnaire, and intelligence quotient (IQ) by the Wechsler abbreviated scale of intelligence. Fifty four percent of young people with ND-CNVs met the threshold for irritability; significantly more than controls (OR = 3.77, CI = 3.07-7.90, p = 5.31 × 10-11). When controlling for the presence of other psychiatric comorbidities, ND-CNV status was still associated with irritability. There was no evidence for a relationship between irritability and IQ. Irritability is an important aspect of the clinical picture in young people with ND-CNVs. This work shows that genetic variation is associated with irritability in young people with ND-CNVs, independent of psychiatric comorbidities or IQ impairment. Clinicians should be aware of this increased risk to inform management and interventions.
Asunto(s)
Variaciones en el Número de Copia de ADN , Genio Irritable , Trastornos del Neurodesarrollo , Humanos , Masculino , Femenino , Adolescente , Trastornos del Neurodesarrollo/genética , Niño , Inteligencia/genética , Estudios de Casos y Controles , HermanosRESUMEN
PURPOSE: Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are conditions that similarly alter cognitive functioning ability and challenge the social interaction, attention, and communication skills of affected individuals. Yet these are distinct neurological conditions that can exhibit diverse characteristics which require different management strategies. It is desirable to develop tools to assist with early distinction so that appropriate early interventions and support may be tailored to an individual's specific requirements. The current diagnostic procedures for ASD and ADHD require a multidisciplinary approach and can be lengthy. This study investigated the potential of electroretinogram (ERG), an eye test measuring retinal responses to light, for rapid screening of ASD and ADHD. METHODS: Previous studies identified differences in ERG amplitude between ASD and ADHD, but this study explored time-frequency analysis (TFS) to capture dynamic changes in the signal. ERG data from 286 subjects (146 control, 94 ASD, 46 ADHD) was analyzed using two TFS techniques. RESULTS: Key features were selected, and machine learning models were trained to classify individuals based on their ERG response. The best model achieved 70% overall accuracy in distinguishing control, ASD, and ADHD groups. CONCLUSION: The ERG to the stronger flash strength provided better separation and the high frequency dynamics (80-300 Hz) were more informative features than lower frequency components. To further improve classification a greater number of different flash strengths may be required along with a discrimination comparison to participants who meet both ASD and ADHD classifications and carry both diagnoses.
RESUMEN
Introduction: The precise epidemiological burden of autism is unknown because of the limited capacity to identify and diagnose the disorder in resource-constrained settings, related in part to a lack of appropriate standardised assessment tools and health care experts. We assessed the reliability, validity, and diagnostic accuracy of the Developmental Diagnostic Dimensional Interview (3Di) in a rural setting on the Kenyan coast. Methods: Using a large community survey of neurodevelopmental disorders (NDDs), we administered the 3Di to 2,110 children aged between 6 years and 9 years who screened positive or negative for any NDD and selected 242 who had specific symptoms suggestive of autism based on parental report and the screening tools for review by a child and adolescent psychiatrist. On the basis of recorded video, a multi-disciplinary team applied the Autism Diagnostic Observation Schedule to establish an autism diagnosis. Internal consistency was used to examine the reliability of the Swahili version of the 3Di, tetrachoric correlations to determine criterion validity, structural equation modelling to evaluate factorial structure and receiver operating characteristic analysis to calculate diagnostic accuracy against Diagnostic Statistical Manual of Mental Disorders (DSM) diagnosis. Results: The reliability coefficients for 3Di were excellent for the entire scale {McDonald's omega (ω) = 0.83 [95% confidence interval (CI) 0.79-0.91]}. A higher-order three-factor DSM-IV-TR model showed an adequate fit with the model, improving greatly after retaining high-loading items and correlated items. A higher-order two-factor DSM-5 model also showed an adequate fit. There were weak to satisfactory criterion validity scores [tetrachoric rho = 0.38 (p = 0.049) and 0.59 (p = 0.014)] and good diagnostic accuracy metrics [area under the curve = 0.75 (95% CI: 0.54-0.96) and 0.61 (95% CI: 0.49-0.73] for 3Di against the DSM criteria. The 3Di had a moderate sensitivity [66.7% (95% CI: 0.22-0.96)] and a good specificity [82.5% (95% CI: 0.74-0.89)], when compared with the DSM-5. However, we observed poor sensitivity [38.9% (95% CI: 0.17-0.64)] and good specificity [83.5% (95% CI: 0.74-0.91)] against DSM-IV-TR. Conclusion: The Swahili version of the 3Di provides information on autism traits, which may be helpful for descriptive research of endophenotypes, for instance. However, for accuracy in newly diagnosed autism, it should be complemented by other tools, e.g., observational clinical judgment using the DSM criteria or assessments such as the Autism Diagnostic Observation Schedule. The construct validity of the Swahili 3Di for some domains, e.g., communication, should be explored in future studies.