Multi-ancestry genome-wide association study of major depression aids locus discovery, fine mapping, gene prioritization and causal inference.

Most genome-wide association studies (GWAS) of major depression (MD) have been conducted in samples of European ancestry. Here we report a multi-ancestry GWAS of MD, adding data from 21 cohorts with 88,316 MD cases and 902,757 controls to previously reported data. This analysis used a range of measures to define MD and included samples of African (36% of effective sample size), East Asian (26%) and South Asian (6%) ancestry and Hispanic/Latin American participants (32%). The multi-ancestry GWAS identified 53 significantly associated novel loci. For loci from GWAS in European ancestry samples, fewer than expected were transferable to other ancestry groups. Fine mapping benefited from additional sample diversity. A transcriptome-wide association study identified 205 significantly associated novel genes. These findings suggest that, for MD, increasing ancestral and global diversity in genetic studies may be particularly important to ensure discovery of core genes and inform about transferability of findings

Central mucoepidermoid carcinoma

Central mucoepidermoid carcinomas (MECs) are extremely rare tumors, comprising 2-3% of all MECs reported in the literature. We report a rare case of clear cell variant of central MEC with calcifications occurring in the left posterior mandible in a 37-year-old male patient

Comparison of the Deacylase and Deacetylase Activity of Zinc-Dependent HDACs

The acetylation status of lysine residues on histone proteins has long been attributed to a balance struck between the catalytic activity of histone acetyl transferases and histone deacetylases (HDAC). HDACs were identified as the sole removers of acetyl post-translational modifications (PTM) of histone lysine residues. Studies into the biological role of HDACs have also elucidated their role as removers of acetyl PTMs from lysine residues of nonhistone proteins. These findings, coupled with high-resolution mass spectrometry studies that revealed the presence of acyl-group PTMs on lysine residues of nonhistone proteins, brought forth the possibility of HDACs acting as removers of both acyl- and acetyl-based PTMs. We posited that HDACs fulfill this dual role and sought to investigate their specificity. Utilizing a fluorescence-based assay and biologically relevant acyl-substrates, the selectivities of zinc-dependent HDACs toward these acyl-based PTMs were identified. These findings were further validated using cellular models and molecular biology techniques. As a proof of principal, an HDAC3 selective inhibitor was designed using HDAC3’s substrate preference. This resulting inhibitor demonstrates nanomolar activity and >30 fold selectivity toward HDAC3 compared to the other class I HDACs. This inhibitor is capable of increasing p65 acetylation, attenuating NF-κB activation, and thereby preventing downstream nitric oxide signaling. Additionally, this selective HDAC3 inhibition allows for control of HMGB-1 secretion from activated macrophages without altering the acetylation status of histones or tubulin

Improving genomic diagnosis of rare pediatric disease in the UK and Ireland

This is the author accepted manuscriptBackground: Pediatric disorders include a range of highly penetrant, genetically heterogeneous conditions amenable to genome-wide diagnostic approaches. Finding a molecular diagnosis is challenging but can have lifelong benefits. Methods: The Deciphering Developmental Disorders (DDD) study recruited >13,500 families with severe, likely monogenic, difficult-to-diagnose developmental disorders from 24 regional genetics services around the UK and Ireland. We collected standardised phenotype data and performed exome sequencing and microarray analysis to investigate novel genetic causes. We developed an iterative variant analysis pipeline, reporting candidate variants to clinical teams for validation, diagnostic interpretation and communication to families. We performed multiple regression analyses evaluating factors affecting probability of diagnosis. Results: We reported ~1 candidate variant per parent-offspring trio and ~2.5 variants per singleton proband. Using clinical and computational approaches to variant classification, we achieved a diagnosis in ~41% (5502 probands), of whom ~76% have a pathogenic de novo variant. Another ~22% have variants of uncertain significance in genes robustly linked with monogenic developmental disorders. Recruitment as a parent-offspring trio had the largest impact on chance of diagnosis (OR=4.70). Probands who were extremely premature (OR=0.39), had in-utero exposure to antiepileptic medications (OR=0.44), or whose mothers had diabetes (OR=0.52) were less likely to be diagnosed, as were those of African ancestry (OR=0.51). Conclusions: The DDD study shows multimodal analysis of genome-wide data has good diagnostic power, even after prior attempts at diagnosis.Health Innovation Challenge FundWellcome Sanger InstituteWellcome Trus

Delivering clinical trials at home: protocol, design and implementation of a direct-to-family paediatric lupus trial

Introduction Direct-to-family clinical trials efficiently provide data while reducing the participation burden for children and their families. Although these trials can offer significant advantages over traditional clinical trials, the process of designing and implementing direct-to-family studies is poorly defined, especially in children with rheumatic disease. This paper provides lessons learnt from the design and implementation of a self-controlled, direct-to-family pilot trial aimed to evaluate the effects of a medication management device on adherence to hydroxychloroquine in paediatric SLE.Methods Several design features accommodate a direct-to-family approach. Participants meeting eligibility criteria from across the USA were identified a priori through a disease registry, and all outcome data are collected remotely. The primary outcome (medication adherence) is evaluated using electronic medication event-monitoring, plasma drug levels, patient questionnaires and pill counts. Secondary and exploratory endpoints include (1) lupus disease activity measured by a remote SLE Disease Activity Index examination and the Systemic Lupus Activity Questionnaire; and (2) hydroxychloroquine pharmacokinetics and pharmacodynamics. Recruitment of the initial target of 20 participants was achieved within 10 days. Due to initial recruitment success, enrolment was increased to 26 participants. Additional participants who were interested were placed on a waiting list in case of dropouts during the study.Discussion and dissemination Direct-to-family trials offer several advantages but present unique challenges. Lessons learnt from the protocol development, design, and implementation of this trial will inform future direct-to-family trials for children and adults with rheumatic diseases. Additionally, the data collected remotely in this trial will provide critical information regarding the accuracy of teleresearch in lupus, the impact of adherence to hydroxychloroquine on disease activity and a pharmacokinetic analysis to inform paediatric-specific dosing of hydroxychloroquine.Trial registration number ClinicalTrials.gov Registry (NCT04358302)