Abundant pleiotropy across neuroimaging modalities identified through a multivariate genome-wide association study.

Genetic pleiotropy is abundant across spatially distributed brain characteristics derived from one neuroimaging modality (e.g. structural, functional or diffusion magnetic resonance imaging [MRI]). A better understanding of pleiotropy across modalities could inform us on the integration of brain function, micro- and macrostructure. Here we show extensive genetic overlap across neuroimaging modalities at a locus and gene level in the UK Biobank (N = 34,029) and ABCD Study (N = 8607). When jointly analysing phenotypes derived from structural, functional and diffusion MRI in a genome-wide association study (GWAS) with the Multivariate Omnibus Statistical Test (MOSTest), we boost the discovery of loci and genes beyond previously identified effects for each modality individually. Cross-modality genes are involved in fundamental biological processes and predominantly expressed during prenatal brain development. We additionally boost prediction of psychiatric disorders by conditioning independent GWAS on our multimodal multivariate GWAS. These findings shed light on the shared genetic mechanisms underlying variation in brain morphology, functional connectivity, and tissue composition.

Dose-dependent social-cognitive effects of intranasal oxytocin delivered with novel Breath Powered device in adults with autism spectrum disorder: a randomized placebo-controlled double-blind crossover trial.

The neuropeptide oxytocin has shown promise as a treatment for symptoms of autism spectrum disorders (ASD). However, clinical research progress has been hampered by a poor understanding of oxytocin's dose-response and sub-optimal intranasal delivery methods. We examined two doses of oxytocin delivered using a novel Breath Powered intranasal delivery device designed to improve direct nose-to-brain activity in a double-blind, crossover, randomized, placebo-controlled trial. In a randomized sequence of single-dose sessions, 17 male adults with ASD received 8 international units (IU) oxytocin, 24IU oxytocin or placebo followed by four social-cognitive tasks. We observed an omnibus main effect of treatment on the primary outcome measure of overt emotion salience as measured by emotional ratings of faces (η2=0.18). Compared to placebo, 8IU treatment increased overt emotion salience (P=0.02, d=0.63). There was no statistically significant increase after 24IU treatment (P=0.12, d=0.4). The effects after 8IU oxytocin were observed despite no significant increase in peripheral blood plasma oxytocin concentrations. We found no significant effects for reading the mind in the eyes task performance or secondary outcome social-cognitive tasks (emotional dot probe and face-morphing). To our knowledge, this is the first trial to assess the dose-dependent effects of a single oxytocin administration in autism, with results indicating that a low dose of oxytocin can significantly modulate overt emotion salience despite minimal systemic exposure.

Age and gender-related differences in emotional and behavioural problems and autistic features in children and adolescents with Down syndrome: a survey-based study of 674 individuals.

BACKGROUND: Recent studies have indicated an increased risk of autism, behavioural and emotional problems and attention-deficit/hyperactivity disorder in individuals with Down syndrome. METHOD: In a large-scale survey-based study, we examined the rates of these problems and their relationship to age and gender, in a sample of 674 individuals (4-18 years) with Down syndrome. The relationship with IQ level was also explored in a subsample (n = 175). The Strengths and Difficulties Questionnaire and the Social Communication Questionnaire were used to assess behavioural and emotional problems and autism traits. RESULTS: On the Strengths and Difficulties Questionnaire, peer problems were the most frequently reported difficulty (48% > cut-off), followed by hyperactivity/inattention (34% > cut-off). On the Social Communication Questionnaire, 37% scored at or above cut-off (≥15) for autism spectrum disorder; 17% were at or above the suggested cut-off (≥22) for autism. Little association between age and behavioural or emotional problems or with severity of autistic symptomatology was found. However, peer problems were more common in adolescents than in junior school children (P < 0.001); Hyperactivity/inattention was less prevalent among adolescents (P < 0.001). CONCLUSIONS: High rates of autistic features, emotional and behavioural problems are documented. These problems are related to age, gender and degree of intellectual disability.

Major involvement of trunk muscles in myotonic dystrophy type 1.

OBJECTIVES: The motor impairments in Myotonic Dystrophy 1 (DM1) are assumed to progress from distal toward proximal parts of the extremities in the Juvenile and Adult forms of DM1. On occasion and late in progress spine deformity is observed. In this study we have examined whether and to what extent trunk muscles are impaired in DM1, and if this impairment is correlated with the duration of the disorder, walking capacity, mobility, balance, and CTG-repeats. MATERIALS & METHODS: Manual muscle testing (MMT) of skeletal muscle strength in trunk and extremities, reassessment of the mutation size, time since first symptom, the 6 min walk test (6MWT), Rivermead mobility index (RIM) and Timed up & go (TUG) were sampled in 38 adult DM1 outpatients. RESULTS: We found significant impairment in trunk muscles. Trunk muscle strength decreased significantly with increasing mutation size (r = -0.64, P < 0.001). Reduced walking capacity, mobility and balance were significantly related to decreased trunk muscle strength. CONCLUSION: DM1 affects trunk muscle groups. The trunk impairments seem to occur relatively early in disease progression. Awareness of trunk impairments may be of importance for everyday functioning and for understanding the risk of injuries due to falls reported among DM1 patients. It may also help in identification of DM1 patients and considered outcome measure in future clinical trials.