Schizophrenia is a serious psychiatric disorder with a broadly undiscovered genetic etiology. Recent studies of de novo mutations (DNM) in schizophrenia and autism have reinforced the hypothesis that rare genetic variation contributes to risk. We carried out exome sequencing on 57 trios with sporadic or familial schizophrenia. In sporadic trios, we observed a ~3.5-fold increase in the proportion of nonsense de novo mutations (DNMs) (0.101 vs. 0.031, empirical P=0.01, BH-corrected P=0.044). These mutations were significantly more likely to occur in genes with highly ranked probabilities of haploinsufficiency (P=0.0029, corrected P=0.006). DNMs of potential functional consequence were also found to occur in genes predicted to be less tolerant to rare variation (P=2.01×10−5, corrected P =2.1×10−3). Genes with DNMs overlapped with genes implicated in autism (e.g. AUTS2, CDH8, MECP2) and intellectual disability (ID) (e.g. HUWE1 and TRAPPC9), supporting a shared genetic etiology between these disorders. Functionally CHD8, MECP2 and HUWE1 converge on epigenetic regulation of transcription suggesting that this may be an important risk mechanism. Our results were consistent in an analysis of additional exome based sequencing studies of other neurodevelopmental disorders. These findings suggest that perturbations in genes which function in the epigenetic regulation of brain development and cognition could have a central role in the susceptibility to, pathogenesis, and treatment of mental disorders.

Schizophrenia (SZ) and autism spectrum disorders (ASDs) are complex neurodevelopmental disorders that may share an underlying pathology suggested by shared genetic risk variants. We sequenced the exonic regions of 215 genes in 147 ASD cases, 273 SZ cases and 287 controls, to identify rare risk mutations. Genes were primarily selected for their function in the synapse and were categorized as: (1) Neurexin and Neuroligin Interacting Proteins, (2) Post-synaptic Glutamate Receptor Complexes, (3) Neural Cell Adhesion Molecules, (4) DISC1 and Interactors and (5) Functional and Positional Candidates. Thirty-one novel loss-of-function (LoF) variants that are predicted to severely disrupt protein-coding sequence were detected among 2 861 rare variants. We found an excess of LoF variants in the combined cases compared with controls (P=0.02). This effect was stronger when analysis was limited to singleton LoF variants (P=0.0007) and the excess was present in both SZ (P=0.002) and ASD (P=0.001). As an individual gene category, Neurexin and Neuroligin Interacting Proteins carried an excess of LoF variants in cases compared with controls (P=0.05). A de novo nonsense variant in GRIN2B was identified in an ASD case adding to the growing evidence that this is an important risk gene for the disorder. These data support synapse formation and maintenance as key molecular mechanisms for SZ and ASD.

Summary We convened a multidisciplinary Working Party on behalf of the Association of Anaesthetists to update the 2011 guidance on the peri‐operative management of people with hip fracture. Importantly, these guidelines describe the core aims and principles of peri‐operative management, recommending greater standardisation of anaesthetic practice as a component of multidisciplinary care. Although much of the 2011 guidance remains applicable to contemporary practice, new evidence and consensus inform the additional recommendations made in this document. Specific changes to the 2011 guidance relate to analgesia, medicolegal practice, risk assessment, bone cement implantation syndrome and regional review networks. Areas of controversy remain, and we discuss these in further detail, relating to the mode of anaesthesia, surgical delay, blood management and transfusion thresholds, echocardiography, anticoagulant and antiplatelet management and postoperative discharge destination. Finally, these guidelines provide links to supplemental online material that can be used at readers' institutions, key references and UK national guidance about the peri‐operative care of people with hip and periprosthetic fractures during the COVID‐19 pandemic.

BackgroundSequencing studies have pointed to the involvement in schizophrenia of rare coding variants in neuronally expressed genes, including activity-regulated cytoskeleton-associated protein (ARC) and N-methyl-D-aspartate receptor (NMDAR) complexes; however, larger samples are required to reveal novel genes and specific biological mechanisms.MethodsWe sequenced 187 genes, selected for prior evidence of association with schizophrenia, in a new dataset of 5207 cases and 4991 controls. Included among these genes were members of ARC and NMDAR postsynaptic protein complexes, as well as voltage-gated sodium and calcium channels. We performed a rare variant meta-analysis with published sequencing data for a total of 11,319 cases, 15,854 controls, and 1136 trios.ResultsWhile no individual gene was significantly associated with schizophrenia after genome-wide correction for multiple testing, we strengthen the evidence that rare exonic variants in the ARC (p = 4.0 × 10–4) and NMDAR (p = 1.7 × 10–5) synaptic complexes are risk factors for schizophrenia. In addition, we found that loss-of-function variants and missense variants at paralog-conserved sites were enriched in voltage-gated sodium channels, particularly the alpha subunits (p = 8.6 × 10–4).ConclusionsIn one of the largest sequencing studies of schizophrenia to date, we provide novel evidence that multiple voltage-gated sodium channels are involved in schizophrenia pathogenesis and confirm the involvement of ARC and NMDAR postsynaptic complexes.

Identifying rare, highly penetrant risk mutations may be an important step in dissecting the molecular etiology of schizophrenia. We conducted a gene-based analysis of large (>100 kb), rare copy-number variants (CNVs) in the Wellcome Trust Case Control Consortium 2 (WTCCC2) schizophrenia sample of 1564 cases and 1748 controls all from Ireland, and further extended the analysis to include an additional 5196 UK controls. We found association with duplications at chr20p12.2 (P = 0.007) and evidence of replication in large independent European schizophrenia (P = 0.052) and UK bipolar disorder case-control cohorts (P = 0.047). A combined analysis of Irish/UK subjects including additional psychosis cases (schizophrenia and bipolar disorder) identified 22 carriers in 11 707 cases and 10 carriers in 21 204 controls [meta-analysis Cochran–Mantel–Haenszel P-value = 2 × 10−4; odds ratio (OR) = 11.3, 95% CI = 3.7, ∞]. Nineteen of the 22 cases and 8 of the 10 controls carried duplications starting at 9.68 Mb with similar breakpoints across samples. By haplotype analysis and sequencing, we identified a tandem ∼149 kb duplication overlapping the gene p21 Protein-Activated Kinase 7 (PAK7, also called PAK5) which was in linkage disequilibrium with local haplotypes (P = 2.5 × 10−21), indicative of a single ancestral duplication event. We confirmed the breakpoints in 8/8 carriers tested and found co-segregation of the duplication with illness in two additional family members of one of the affected probands. We demonstrate that PAK7 is developmentally co-expressed with another known psychosis risk gene (DISC1) suggesting a potential molecular mechanism involving aberrant synapse development and plasticity.