The role of SH3BP2 in the pathophysiology of cherubism

Cherubism is a rare bone dysplasia that is characterized by symmetrical bone resorption limited to the jaws. Bone lesions are filled with soft fibrous giant cell-rich tissue that can expand and cause severe facial deformity. The disorder typically begins in children at ages of 2-5 years and the bone resorption and facial swelling continues until puberty; in most cases the lesions regress spontaneously thereafter. Most patients with cherubism have germline mutations in the gene encoding SH3BP2, an adapter protein involved in adaptive and innate immune response signaling. A mouse model carrying a Pro416Arg mutation in SH3BP2 develops osteopenia and expansile lytic lesions in bone and some soft tissue organs. In this review we discuss the genetics of cherubism, the biological functions of SH3BP2 and the analysis of the mouse model. The data suggest that the underlying cause for cherubism is a systemic autoinflammatory response to physiologic challenges despite the localized appearance of bone resorption and fibrous expansion to the jaws in humans

Cherubism: best clinical practice

Cherubism is a skeletal dysplasia characterized by bilateral and symmetric fibro-osseous lesions limited to the mandible and maxilla. In most patients, cherubism is due to dominant mutations in the SH3BP2 gene on chromosome 4p16.3. Affected children appear normal at birth. Swelling of the jaws usually appears between 2 and 7 years of age, after which, lesions proliferate and increase in size until puberty. The lesions subsequently begin to regress, fill with bone and remodel until age 30, when they are frequently not detectable

Rectal Swabs as an Alternative Sample Collection Method to Bulk Stool for the Real-Time PCR Detection of \u3ci\u3eGiardia duodenalis\u3c/i\u3e

Though bulk stool remains the gold standard specimen type for enteropathogen diagnosis, rectal swabs may offer comparable sensitivity with greater ease of collection for select pathogens. This study sought to evaluate the validity and reproducibility of rectal swabs as a sample collection method for the molecular diagnosis of Giardia duodenalis. Paired rectal swab and bulk stool samples were collected from 86 children ages 0–4 years living in southwest Niger, with duplicate samples collected among a subset of 50 children. Infection was detected using a previously validated real-time PCR diagnostic targeting the small subunit ribosomal RNA gene. Giardia duodenalis was detected in 65.5% (55/84) of bulk stool samples and 44.0% (37/84) of swab samples. The kappa evaluating test agreement was 0.81 (95% CI: 0.54–1.00) among duplicate stool samples (N = 49) and 0.75 (95% CI: 0.47–1.00) among duplicate rectal swabs (N = 48). Diagnostic sensitivity was 93% (95% CI: 84–98) by bulk stool and 63% (95% CI: 49–75) by rectal swabs. When restricting to the lowest three quartiles of bulk stool quantitation cycle values (an indication of relatively high parasite load), sensitivity by rectal swabs increased to 78.0% (95% CI: 64–89, P \u3c 0.0001). These findings suggest that rectal swabs provide less sensitive and reproducible results than bulk stool for the real-time PCR diagnosis of G. duodenalis. However, their fair sensitivity for higher parasite loads suggests that swabs may be a useful tool for detecting higher burden infections when stool collection is excessively expensive or logistically challenging

Deciphering osteoarthritis genetics across 826,690 individuals from 9 populations

Osteoarthritis affects over 300 million people worldwide. Here, we conduct a genome-wide association study meta-analysis across 826,690 individuals (177,517 with osteoarthritis) and identify 100 independently associated risk variants across 11 osteoarthritis phenotypes, 52 of which have not been associated with the disease before. We report thumb and spine osteoarthritis risk variants and identify differences in genetic effects between weight-bearing and non-weight-bearing joints. We identify sex-specific and early age-at-onset osteoarthritis risk loci. We integrate functional genomics data from primary patient tissues (including articular cartilage, subchondral bone, and osteophytic cartilage) and identify high-confidence effector genes. We provide evidence for genetic correlation with phenotypes related to pain, the main disease symptom, and identify likely causal genes linked to neuronal processes. Our results provide insights into key molecular players in disease processes and highlight attractive drug targets to accelerate translation

Deciphering osteoarthritis genetics across 826,690 individuals from 9 populations

Funding Information: T.R.G. and J.Z. receive research funding from GlaxoSmithKline. T.R.G. receives research funding from Biogen. U.S., K.S., L. Stefánsdóttir, G.B., S.H.L., U.T., and G. T. are employed by deCODE genetics/Amgen Inc. A.M.V. is a consultant for Zoe Global Ltd. All other authors report no competing interests. All Regeneron Genetics Center banner authors are current employees and/or stockholders of Regeneron Pharmaceuticals. Funding Information: We thank Nigel W. Rayner and Ahmed Elhakeem for their input. This research was conducted using the UK Biobank Resource under application numbers 9979 and 23359. G.D.S. and T.R.G. work in the Medical Research Council Integrative Epidemiology Unit at the University of Bristol MC_UU_00011/1&4. A.M.V. is funded by the NIHR Nottingham BRC. J.Z. is funded by a Vice-Chancellor Fellowship from the University of Bristol. This research was also funded by the UK Medical Research Council Integrative Epidemiology Unit (MC_UU_00011/4). Study design and project coordination, E. Zeggini; Writing Group, U.S. J.B.J.v.M. J.M.W. M.T.M.L. K.S.E.C. L.S. C.G.B. K.H. Y.Z. R.C.d.A. L. Stef?nsd?ttir, E. Zeggini, A.P.M. G.T. P.C.S. J.Z. and T.R.G.; Core Analyses, C.G.B. K. Hatzikotoulas, L. Southam, L. Stef?nsd?ttir, Y.Z. R.C.d.A. T.T.W. J.Z. A.H. M.T.-L. and J.M.W.; Individual Study Design and Principal Investigators, E. Zeggini, U.S. J.B.J.v.M. M.T.M.L. I.M. J.M.W. T.E. K. Hveem, S.I. K.S.E.C. A.T. A.M.V. K.S. P.E.S. P.C. G.D.S. J.H.T. T.R.G. S.A.L. G.C.B. A.G.U. U.T. P.K. J.H.K. arcOGEN Consortium, HUNT All-In Pain, ARGO Consortium, and Regeneron Genetics Center; Analyses, Genotyping, and Phenotyping in Individual Studies, C.G.B. K.H. L. Southam, J.M.W. L. Stef?nsd?ttir, Y.Z. R.C.d.A. T.T.W. J.Z. A.H. M.T.-L. A.H.S. C.T. E. Zengini, A.B. G.T. G.B. H.J. T.I. R.M. H.T. M.K. M.T. R.R.G.H.H.N. M.M. J.P.Y.C. D.S. J.-A.Z. A.L. M.B.J. L.F.T. B.W. M.E.G. J.S. M.S. G.A. A.G. S.H.L. arcOGEN Consortium, HUNT All-In Pain, ARGO Consortium, and Regeneron Genetics Center. All authors contributed to the final version of the manuscript. T.R.G. and J.Z. receive research funding from GlaxoSmithKline. T.R.G. receives research funding from Biogen. U.S. K.S. L. Stef?nsd?ttir, G.B. S.H.L. U.T. and G. T. are employed by deCODE genetics/Amgen Inc. A.M.V. is a consultant for Zoe Global Ltd. All other authors report no competing interests. All Regeneron Genetics Center banner authors are current employees and/or stockholders of Regeneron Pharmaceuticals. Funding Information: We thank Nigel W. Rayner and Ahmed Elhakeem for their input. This research was conducted using the UK Biobank Resource under application numbers 9979 and 23359. G.D.S. and T.R.G. work in the Medical Research Council Integrative Epidemiology Unit at the University of Bristol MC_UU_00011/1&4. A.M.V. is funded by the NIHR Nottingham BRC . J.Z. is funded by a Vice-Chancellor Fellowship from the University of Bristol . This research was also funded by the UK Medical Research Council Integrative Epidemiology Unit ( MC_UU_00011/4 ). Publisher Copyright: © 2021 The AuthorsOsteoarthritis affects over 300 million people worldwide. Here, we conduct a genome-wide association study meta-analysis across 826,690 individuals (177,517 with osteoarthritis) and identify 100 independently associated risk variants across 11 osteoarthritis phenotypes, 52 of which have not been associated with the disease before. We report thumb and spine osteoarthritis risk variants and identify differences in genetic effects between weight-bearing and non-weight-bearing joints. We identify sex-specific and early age-at-onset osteoarthritis risk loci. We integrate functional genomics data from primary patient tissues (including articular cartilage, subchondral bone, and osteophytic cartilage) and identify high-confidence effector genes. We provide evidence for genetic correlation with phenotypes related to pain, the main disease symptom, and identify likely causal genes linked to neuronal processes. Our results provide insights into key molecular players in disease processes and highlight attractive drug targets to accelerate translation.Peer reviewe

Articular cartilage repair: Current needs, methods and research directions

Articular cartilage is a highly specialized tissue whose remarkable properties of deformability, resistance to mechanical loading, and low-friction gliding are essential to joint function. Due to its role as a cushion in bone articulation, articular cartilage is subject to many types of damaging insults, including decades of wear and tear, and acute joint injuries. However, this built-for-life tissue has a very poor intrinsic ability in adulthood to durably heal defects created by damaging insults. Consequently, articular cartilage progressively deteriorates and is eventually eroded, exposing the subchondral bone to the joint space, triggering inflammation and osteophyte development, and generating severe pain and joint incapacitation. The disease is called osteoarthritis (OA) and is today the leading cause of pain and disability in the human population. Researchers and clinicians have worked for decades to develop strategies to treat OA and restore joint function, but they are still far from being able to offer patients effective preventive or restorative treatments. Novel ideas, knowledge and technologies that nurture hope for major new breakthroughs are therefore sought. In this review, we first outline the composition, structure, and functional properties of normal human adult articular cartilage, as a reference for tissue conservation and regenerative strategies. We then describe current options that have been used clinically and in pre-clinical trials to treat osteoarthritic patients, and we discuss the benefits and inadequacies of these treatment options. Next, we review research efforts that are currently ongoing to try and achieve durable repair of functional cartilage tissue. Methods include engineering of tissue implants and we discuss the needs and options for tissue scaffolds, cell sources, and growth and differentiation factors to generate de novo or repair bona fide articular cartilage