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Simple Summary: Zebrafish (Danio rerio) younger than five days post fertilization are not protected by legislation, and protocols for their euthanasia are poorly explored. In the present paper, we assess the euthanasic efficacy of anesthetic overdose, hypothermic shock, and electrical stunning on zebrafish at <12 h post fertilization, and 1 and 4 days post fertilization utilizing laboratories in different countries. Based on the survival/recovery rates 24 h after treatment, the most effective methods were an overdose with either clove oil or lidocaine with ethanol, and electrical stunning. For the oldest larvae, signs of aversion during treatment demonstrated that all the tested anesthetics, except lidocaine, induced aversive behavior. Therefore, the most suited anesthetic treatment was lidocaine hydrochloride, 1 g/L, buffered with 2 g/L of sodium bicarbonate and mixed with 50 mL/L of ethanol. Electrical stunning also euthanized embryos and larvae efficiently and without signs of aversion; this method is new and needs further assessment in other laboratories to draw firm conclusions. Euthanasia in zebrafish (Danio rerio) younger than 5 days post fertilization (dpf) is poorly described in the literature, and standardized protocols are lacking, most likely because larvae not capable of independent feeding are often not protected under national legislations. We assessed the euthanasia efficacy in laboratories in different countries of a one hour anesthetic overdose immersion with buffered lidocaine hydrochloride (1 g/L, with or without 50 mL/L of ethanol), buffered tricaine (1 g/L), clove oil (0.1%), benzocaine (1 g/L), or 2-phenoxyethanol (3 mL/L), as well as the efficacy of hypothermic shock (one hour immersion) and electrical stunning (for one minute), on zebrafish at <12 h post fertilization (hpf), 24 hpf, and 4 dpf. Based on the survival/recovery rates 24 h after treatment, the most effective methods were clove oil, lidocaine with ethanol, and electrical stunning. For 4 dpf larvae, signs of aversion during treatment demonstrated that all anesthetics, except lidocaine, induced aversive behavior. Therefore, the most suited euthanasic treatment was lidocaine hydrochloride 1 g/L, buffered with 2 g/L of sodium bicarbonate and mixed with 50 mL/L of ethanol, which euthanized both embryos and larvae in an efficient and stress-free manner. Electrical stunning also euthanized embryos and larvae efficiently and without signs of aversion; this method needs further assessment in other laboratories to draw firm conclusions. [ABSTRACT FROM AUTHOR]

A homozygous nonsense mutation in the cereblon (CRBN) gene results in autosomal recessive, nonsyndromic intellectual disability that is devoid of other phenotypic features, suggesting a critical role of CRBN in mediating learning and memory. In this study, vve demonstrate that adult male Crbn knock-out (CrlmK0) mice exhibit deficits in hippocampal-dependent learning and memory tasks that are recapitulated by focal knock-out of Crbn in the adult dorsal hippocampus, with no changes in social or repetitive behavior. Cellular studies identify deficits in long-term potentiation at Schaffer collateral CA1 synapses. We further show that Crbn is robustly expressed in the mouse hippocampus and CrbnK0 mice exhibit hyperphosphorylated levels of AMPKα (Thr 172). Examination of processes downstream of AMP-activated protein kinase (AMPK) finds that Crbnko mice have a selective impairment in mediators of the mTORCl translation initiation pathway in parallel with lower protein levels of postsynaptic density glutamatergic proteins and higher levels of excitatory presynaptic markers in the hippocampus with no change in markers of the unfolded protein response or autophagy pathways. Acute pharmacological inhibition of AMPK activity in adult CrbnK0 mice rescues learning and memory deficits and normalizes hippocampal mTORCl activity and postsynaptic glutamatergic proteins without altering excitatory presynaptic markers. Thus, this study identifies that loss of Crbn results in learning, memory, and synaptic defects as a consequence of exaggerated AMPK activity, inhibition of mTORCl signaling, and decreased glutamatergic synaptic proteins. Thus, CrbnK0 mice serve as an ideal model of intellectual disability to further explore molecular mechanisms of learning and memory. [ABSTRACT FROM AUTHOR]

Background/Objectives: Brief cognitive screens lack the sensitivity to detect mild cognitive impairment (MCI) or support differential diagnoses. The objective of this study was to validate the 10‐minute, tablet‐based University of California, San Francisco (UCSF) Brain Health Assessment (BHA) to overcome these limitations. Design: Cross‐sectional. Setting: UCSF Memory and Aging Center. Participants: Older adults (N = 347) (neurologically healthy controls (n = 185), and individuals diagnosed with MCI (n = 99), dementia (n = 42), and as normal with concerns (n = 21)). Measurements: The BHA includes subtests of memory, executive function and speed, visuospatial skills, and language and an optional informant survey. Participants completed the Montreal Cognitive Assessment (MoCA) and criterion‐standard neuropsychological tests. Standardized structural 3T brain magnetic resonance imaging was performed in 145 participants. Results: At a fixed 85% specificity rate, the BHA had 100% sensitivity to dementia and 84% to MCI; the MoCA had 75% sensitivity to dementia and 25% to MCI. The BHA had 83% sensitivity to MCI likely due to AD and 88% to MCI unlikely due to AD, and the MoCA had 58% sensitivity to MCI likely AD and 24% to MCI unlikely AD. The BHA subtests demonstrated moderate to high correlations with the criterion‐standard tests from their respective cognitive domains. Memory test performance correlated with medial temporal lobe volumes; executive and speed with frontal, parietal, and basal ganglia volumes; and visuospatial with right parietal volumes. Conclusion: The BHA had excellent combined sensitivity and specificity to detect dementia and MCI, including MCI due to diverse etiologies. The subtests provide efficient, valid measures of neurocognition that are critical in making a differential diagnosis. [ABSTRACT FROM AUTHOR]

Copy-number variations cause genomic disorders. Triplications, unlike deletions and duplications, are poorly understood because of challenges in molecular identification, the choice of a proper model system for study, and awareness of their phenotypic consequences. We investigated the genomic disorder Charcot-Marie-Tooth disease type 1A (CMT1A), a dominant peripheral neuropathy caused by a 1.4 Mb recurrent duplication occurring by nonallelic homologous recombination. We identified CMT1A triplications in families in which the duplication segregates. The triplications arose de novo from maternally transmitted duplications and caused a more severe distal symmetric polyneuropathy phenotype. The recombination that generated the triplication occurred between sister chromatids on the duplication-bearing chromosome and could accompany gene conversions with the homologous chromosome. Diagnostic testing for CMT1A (n = 20,661 individuals) identified 13% (n = 2,752 individuals) with duplication and 0.024% (n = 5 individuals) with segmental tetrasomy, suggesting that triplications emerge from duplications at a rate as high as ∼1:550, which is more frequent than the rate of de novo duplication. We propose that individuals with duplications are predisposed to acquiring triplications and that the population prevalence of triplication is underascertained. [Copyright &y& Elsevier]

Abstract: A nonsense mutation in the human cereblon gene (CRBN) causes a mild type of autosomal recessive non-syndromic intellectual disability (ID). Animal studies show that crbn is a cytosolic protein with abundant expression in the hippocampus (HPC) and neocortex (CTX). Its diverse functions include the developmental regulation of ion channels at the neuronal synapse, the mediation of developmental programs by ubiquitination, and a target for herpes simplex type I virus in HPC neurons. To test the hypothesis that anomalous CRBN expression leads to HPC-mediated memory and learning deficits, we generated germ-line crbn knock-out mice (crbn −/−). We also inactivated crbn in forebrain neurons in conditional knock-out mice in which crbn exons 3 and 4 are deleted by cre recombinase under the direction of the Ca 2+ /calmodulin-dependent protein kinase II alpha promoter (CamKII cre/+, crbn −/−). crbn mRNA levels were negligible in the HPC, CTX, and cerebellum (CRBM) of the crbn −/− mice. In contrast, crbn mRNA levels were reduced 3- to 4-fold in the HPC, CTX but not in the CRBM in CamKII cre/+, crbn −/− mice as compared to wild type (CamKII cre/+, crbn +/+). Contextual fear conditioning showed a significant decrease in the percentage of freezing time in CamKII cre/+, crbn −/− and crbn −/− mice while motor function, exploratory motivation, and anxiety-related behaviors were normal. These findings suggest that CamKII cre/+, crbn −/− mice exhibit selective HPC-dependent deficits in associative learning and supports the use of these mice as in vivo models to study the functional consequences of CRBN aberrations on memory and learning in humans. [Copyright &y& Elsevier]

The study of inherited retinal diseases has advanced our knowledge of the cellular and molecular mechanisms involved in sensory neural signaling. Dysfunction of two specific sensory modalities, vision and proprioception, characterizes the phenotype of the rare, autosomal-recessive disorder posterior column ataxia and retinitis pigmentosa (PCARP). Using targeted DNA capture and high-throughput sequencing, we analyzed the entire 4.2 Mb candidate sequence on chromosome 1q32 to find the gene mutated in PCARP in a single family. Employing comprehensive bioinformatic analysis and filtering, we identified a single-nucleotide coding variant in the feline leukemia virus subgroup C cellular receptor 1 (FLVCR1), a gene encoding a heme-transporter protein. Sanger sequencing confirmed the FLVCR1 mutation in this family and identified different homozygous missense mutations located within the protein''s transmembrane channel segment in two other unrelated families with PCARP. To determine whether the selective pathologic features of PCARP correlated with FLVCR1 expression, we examined wild-type mouse Flvcr1 mRNA levels in the posterior column of the spinal cord and the retina via quantitative real-time reverse-transcriptase PCR. The Flvcr1 mRNA levels were most abundant in the retina, followed by the posterior column of the spinal cord and other brain regions. These results suggest that aberrant FLVCR1 causes a selective degeneration of a subpopulation of neurons in the retina and the posterior columns of the spinal cord via dysregulation of heme or iron homeostasis. This finding broadens the molecular basis of sensory neural signaling to include common mechanisms that involve proprioception and vision. [Copyright &y& Elsevier]

Background: Primary care providers (PCPs) are typically the first to screen and evaluate patients for neurocognitive disorders (NCDs), including mild cognitive impairment and dementia. However, data on PCP attitudes and evaluation and management practices are sparse. Our objective was to quantify perspectives and behaviors of PCPs and neurologists with respect to NCD evaluation and management.Methods: A cross-sectional survey with 150 PCPs and 50 neurologists in the United States who evaluated more than 10 patients over age 55 per month. The 51-item survey assessed clinical practice characteristics, and confidence, perceived barriers, and typical practices when diagnosing and managing patients with NCDs.Results: PCPs and neurologists reported similar confidence and approaches to general medical care and laboratory testing. Though over half of PCPs performed cognitive screening or referred patients for cognitive testing in over 50% of their patients, only 20% reported high confidence in interpreting results of cognitive tests. PCPs were more likely to order CT scans than MRIs, and only 14% of PCPs reported high confidence interpreting brain imaging findings, compared to 70% of specialists. Only 21% of PCPs were highly confident that they correctly recognized when a patient had an NCD, and only 13% were highly confident in making a specific NCD diagnosis (compared to 72 and 44% for neurologists, both p < 0.001). A quarter of all providers identified lack of familiarity with diagnostic criteria for NCD syndromes as a barrier to clinical practice.Conclusions: This study demonstrates how PCPs approach diagnosis and management of patients with NCDs, and identified areas for improvement in regards to cognitive testing and neuroimaging. This study also identified all providers' lack of familiarity with published diagnostic criteria for NCD syndromes. These findings may inform the development of new policies and interventions to help providers improve the efficacy of their decision processes and deliver better quality care to patients with NCDs. [ABSTRACT FROM AUTHOR]

We present the first use of a bioengineered mammalian transposase system derived from Myotis lucifugus (bMLT) for integration of expression vectors into the CHO genome, focusing on GFP and trastuzumab production. Initially, CHO-K1 cells are transfected with a GFP reporter and varying amounts of bMLT DNA or mRNA. GFP expression is monitored over 17 weeks without selective pressure. Transfection efficiency shows around 90% GFP-positive cells, but in control cultures GFP expression disappears after 10 days. In contrast, bMLT-treated cultures maintain stable GFP expression, with a dose-dependent integration efficiency of up to 60%. The highest GFP expression per cell is observed with lower bMLT amounts. Next-generation sequencing analysis reveals multiple integration sites, with 85% correctly integrated sequences. Next, CHO-GS -/- cells are transfected with trastuzumab and bMLT DNA or mRNA. Cells are selected in glutamine-free medium with varying methionine sulfoximine (MSX) concentrations. Recovery is faster without MSX, and no difference is observed between bMLT DNA and mRNA transfections. bMLT-treated cultures show a higher percentage of trastuzumab-secreting cells (40%-55%) compared with random integration (0.3%-0.5%). The absence of insulators in the trastuzumab plasmid likely affects selection behavior, as integration in heterochromatic regions results in gene repression. Overall, bMLT-mediated integration proves efficient, generating stable cell pools with high expression profiles without selective pressure. The integration sites' genomic location significantly impacts productivity, with favorable regions supporting higher expression. This method shows promise for the rapid and efficient generation of high-producing cell lines and for rapid evaluation of long-term effects of different cell engineering approaches., (© 2025 SALIOGEN THERAPEUTICS, INC. and The Author(s). Biotechnology Progress published by Wiley Periodicals LLC on behalf of American Institute of Chemical Engineers.)

Background: Pancarpal arthrodesis (PCA) is a commonly performed procedure in the UK. However, it is not known whether working dogs in the UK and other European countries with carpal injuries that have undergone unilateral PCA are able to return to working ability as determined by the owner. Medical records from a referral hospital in the UK were reviewed retrospectively for cases of working dogs treated using unilateral PCA. Case files and radiographs were retrospectively analysed for cause of injury, diagnosis, and complications. The ability of the dog to work after surgery and owner satisfaction with the outcome were assessed using telephone questionnaire., Results: 50% (5/10, 50%) owners stated their dog could perform normal duties, 4/10 (40%) could perform most duties with some allowances. Outcome was not as good for dogs working on steep, uneven fell terrain. 80% (8/10, 80%) owners rated the level of post-operative lameness as unaffected with a normal gait. 90% (9/10, 90%) owners were either very satisfied or satisfied with the outcome of the procedure, and 90% owners stated the financial investment was worthwhile., Conclusions: Unilateral PCA carries a good prognosis for working dogs with high owner satisfaction. Caution should be advised for dogs expected to work on steep, uneven fell terrain., (© 2024. The Author(s).)

Stargardt macular dystrophy (Stargardt disease; STGD1; OMIM 248200) is the most prevalent inherited macular dystrophy. STGD1 is an autosomal recessive disorder caused by multiple pathogenic sequence variants in the large ABCA4 gene (OMIM 601691). Major advances in understanding both the clinical and molecular features, as well as the underlying pathophysiology, have culminated in many completed, ongoing and planned human clinical trials of novel therapies.The aims of this concise review are to describe (1) the detailed phenotypic and genotypic characteristics of the disease, multimodal imaging findings, natural history of the disease, and pathogenesis, (2) the multiple avenues of research and therapeutic intervention, including pharmacological, cellular therapies and diverse types of genetic therapies that have either been investigated or are under investigation and (3) the exciting novel therapeutic approaches on the translational horizon that aim to treat STGD1 by replacing the entire 6.8 kb ABCA4 open reading frame., Competing Interests: Competing interests: Disclosures/Conflicts of Interest: KF: Consultant (category C): Astellas Pharma, Kubota Pharmaceutical, Acucela, Novartis, Janssen, Sanofi, NightstaRx, Stargazer, SalioGen Therapeutics, Belite Bio, Alnylam, Restore Vision, FRESTKF: Clinical trial/Research support (category F): National Institute for Health and Care Research, Foundation Fighting Blindness, Janssen, Novartis, Janssen, AstellasPY: Consultant (category C): 4D Molecular Therapeutics, Adverum, AGTC, Annexon Bio, EcoR1, Exegenesis Bio, ExpertConnect, Foundation Fighting Blindness (SAB), Guidepoint, Iveric Bio, Janssen, MeiraGTx, Nanoscope Therapeutics (SAB), Otonomy, ProQR, Saliogen Therapeutics, TeamedOn, VederePY: Clinical trial/Research support (category F): 4D Molecular Therapeutics, Acucela, Atsena, AGTC, Biogen, Editas, Foundation Fighting Blindness, Iveric bio, Ocugen, ProQR, Reneuron, Sanofi, SparkNW: Consultant (category C): Complement Therapeutics, Nidek, SalioGen Therapeutics, Stealth, Syncona, TopconNW: Clinical trial/Research support (category F): Carl Zeiss Meditec, Heidelberg, NidekNW: N Waheed is a board member of Iolyx Therapeutics, a shareholder in Ocudyne, and a previous shareholder of Gyroscope Therapeutics. JH, JTL and CC: JH and JTL are currently full-time employees and stock option holders of SalioGen Therapeutics. C Clary is a former employee of SalioGen Therapeutics.DC: D Curtiss is a full-time employee and stock option holder of AGTC. YL, YF-Y: YL and YF-Y have no conflicts of interest to disclose. MM: Consultant (category C): Acucela, MeiraGTx, Janssen, Stargazer, Claris Bio, SalioGen Therapeutics, Belite Bio and Alnylam. MM holds equity in MeiraGTx., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

Over the past 40 years, there has been considerable research into the management and treatment of atherogenic lipid disorders. Although the majority of treatments and management strategies for cardiovascular disease (CVD) center around targeting low-density lipoprotein cholesterol (LDL-C), there is mounting evidence for the residual CVD risk attributed to high triglyceride (TG) and lipoprotein(a) (Lp(a)) levels despite the presence of lowered LDL-C levels. Among the biological mechanisms for clearing TG-rich lipoproteins, the VLDL receptor (VLDLR) plays a key role in the trafficking and metabolism of lipoprotein particles in multiple tissues, but it is not ordinarily expressed in the liver. Since VLDLR is capable of binding and internalizing apoE-containing TG-rich lipoproteins as well as Lp(a), hepatic VLDLR expression has the potential for promoting clearance of these atherogenic particles from the circulation and managing the residual CVD risk not addressed by current lipid lowering therapies. This review provides an overview of VLDLR function and the potential for developing a genetic medicine based on liver-targeted VLDLR gene expression., (Copyright © 2023 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Zebrafish are often euthanized by overdose of anaesthesia. However, fish may have aversion towards some anaesthetics, and protocol efficacy varies between species. Using wild type adult Danio rerio , we assessed time to loss of opercular beat, righting, and startle reflexes during induction of anaesthetic overdose by either tricaine (0.5 g/L or 1 g/L), benzocaine (1 g/L), 2-phenoxyethanol (3 mL/L), clove oil (0.1%), isoeugenol (540 mg/L), lidocaine hydrochloride (1 g/L), or etomidate (50 mg/L). Initial screening demonstrated that benzocaine and buffered lidocaine hydrochloride achieved the fastest loss of reflexes. The rapid induction times were confirmed when retesting using larger batches of fish. The fastest induction was obtained with 1 g/L lidocaine hydrochloride buffered with 2 g/L NaHCO 3 , in which all adult zebrafish lost reflexes in less than 2 min. Next, we monitored signs of distress during benzocaine or buffered lidocaine hydrochloride overdose induction. The results indicated that buffered lidocaine hydrochloride caused significantly less aversive behaviors than benzocaine. Finally, we tested several buffers to refine the lidocaine hydrochloride immersion. The most efficient buffer for euthanasia induction using 1g/L lidocaine hydrochloride was 2 g/L NaHCO 3 with 50 mL/L 96% ethanol, inducing immobility in less than 10 s and with only 2% of adult zebrafish displaying aversive behaviors during treatment.

The current standard of care for the treatment of flow-limiting calcific iliac artery disease is balloon angioplasty and subsequent stent placement. However, the presence of calcified lesions may prevent adequate stent expansion or impede the delivery of large bore devices, such as those for transcatheter aortic valve replacement or endovascular aneurysm repair implants. Plaque modification through vessel preparation with orbital atherectomy may enable stent expansion and subsequent proper large device delivery with low rates of procedural complications. A retrospective, single center, case series of 13 subjects treated with orbital atherectomy in iliac arteries to enable large bore device delivery was conducted. Patients were selected for treatment based on iliac artery disease or inability to deliver devices. The procedural complication rate was defined as the composite of flow-limiting dissection, perforation, slow flow, vessel closure, spasm, embolism, and thrombosis. Technical success was assessed as angiographic luminal gain and subsequent successful delivery of large bore devices through the treatment area, as well as freedom from procedural complications. Orbital atherectomy vessel preparation of severely calcified iliac artery lesions resulted in adequate stent expansion safely and enabled delivery of rigid/large profile devices. Further studies are warranted to evaluate patient selection criteria, as well as long-term efficacy and safety rates of orbital atherectomy in the iliac artery., Competing Interests: Declaration of conflicting interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: S.R. has a consulting agreement with Cardiovascular Systems, Inc. (CSI). D.P. has no declarations of interest. B.J.M., J.H., and H.D. are employees of CSI. These conflicts did not affect the study design, conduct, or reporting., (© The Author(s) 2020.)

Background: Despite its high prevalence, malnutrition in hospitalized patients often goes unrecognized and undertreated., Local Problem: A hospital system sought to improve nutrition care by implementing a quality improvement initiative. Nurses screened patients upon admission using the Malnutrition Screening Tool and initiated oral nutrition supplements for patients at risk., Methods: We retrospectively reviewed the medical records of 20 697 adult patients to determine whether early initiation of nutrition therapy had reduced hospital length of stay and 30-day readmission rates., Results: We found the average time from hospital admission to oral nutrition supplement initiation was reduced by 20 hours (20.8%) after the quality improvement initiative was introduced (P < .01). Length of stay decreased 0.88 days (P < .05) more for patients at nutritional risk than patients not at nutritional risk; the probability of 30-day hospital readmission did not differ between groups., Conclusion: These results highlight the importance of adequate nutrition screening, diagnosis, and treatment for hospitalized patients.

Background: Frontotemporal lobar degeneration (FTLD) is a leading cause of dementia, and elucidating its genetic underpinnings is critical. FTLD research centers typically recruit patient cohorts that are limited by the center's specialty and the ways in which its geographic location affects the ethnic makeup of research participants. Novel sources of data are needed to get population estimates of the contribution of variants in known FTLD-associated genes., Methods: We compared FLTD-associated genetic variants in microtubule-associated protein tau ( MAPT ), progranulin ( GRN ), and chromosome nine open reading frame 72 ( C9ORF72 ) from an academic research cohort and a commercial clinical genetics laboratory. Pathogenicity was assessed using guidelines of the American College of Medical Genetics and Genomics and a rule-based DNA variant assessment system. We conducted chart reviews on patients with novel or rare disease-associated variants., Results: A total of 387 cases with FTLD-associated variants from the commercial (n=2,082) and 78 cases from the academic cohort (n=2,089) were included for analysis. In the academic cohort, the most frequent pathogenic variants were C9ORF72 expansions (63%, n=49), followed by GRN (26%, n=20) and MAPT (11%, n=9). Each gene's contribution to disease was similarly ranked in the commercial laboratory but differed in magnitude: C9ORF72 (89%, n=345), GRN (6%, n=24), and MAPT (5%, n=19). Of the 37 unique GRN / MAPT variants identified, only six were found in both cohorts. Clinicopathological data from patients in the academic cohort strengthened classification of two novel GRN variant as pathogenic (p.Pro166Leufs*2, p.Gln406*) and one GRN variant of unknown significance as a possible rare risk variant (p.Cys139Arg)., Conclusion: Differences in gene frequencies and identification of unique pathogenic alleles in each cohort demonstrate the importance of data sharing between academia and community laboratories. Using shared data sources with well-characterized clinical phenotypes for individual variants can enhance interpretation of variant pathogenicity and inform clinical management of at-risk patients and families., Competing Interests: The other authors report no conflicts of interest in this work.

We developed a rules-based scoring system to classify DNA variants into five categories including pathogenic, likely pathogenic, variant of uncertain significance (VUS), likely benign, and benign. Over 16,500 pathogenicity assessments on 11,894 variants from 338 genes were analyzed for pathogenicity based on prediction tools, population frequency, co-occurrence, segregation, and functional studies collected from internal and external sources. Scores were calculated by trained scientists using a quantitative framework that assigned differential weighting to these five types of data. We performed descriptive and comparative statistics on the dataset and tested interobserver concordance among the trained scientists. Private variants defined as variants found within single families (n = 5,182), were either VUS (80.5%; n = 4,169) or likely pathogenic (19.5%; n = 1,013). The remaining variants (n = 6,712) were VUS (38.4%; n = 2,577) or likely benign/benign (34.7%; n = 2,327) or likely pathogenic/pathogenic (26.9%, n = 1,808). Exact agreement between the trained scientists on the final variant score was 98.5% [95% confidence interval (CI) (98.0, 98.9)] with an interobserver consistency of 97% [95% CI (91.5, 99.4)]. Variant scores were stable and showed increasing odds of being in agreement with new data when re-evaluated periodically. This carefully curated, standardized variant pathogenicity scoring system provides reliable pathogenicity scores for DNA variants encountered in a clinical laboratory setting., (© 2015 The Authors. **Human Mutation published by Wiley Periodicals, Inc.)

We compare molecular combing to Southern blot in the analysis of the facioscapulohumeral muscular dystrophy type 1 locus (FSHD1) on chromosome 4q35-qter (chr 4q) in genomic DNA specimens sent to a clinical laboratory for FSHD testing. A de-identified set of 87 genomic DNA specimens determined by Southern blot as normal (n = 71), abnormal with D4Z4 macrosatellite repeat array contractions (n = 7), indeterminate (n = 6), borderline (n = 2), or mosaic (n = 1) was independently re-analyzed by molecular combing in a blinded fashion. The molecular combing results were identical to the Southern blot results in 75 (86%) of cases. All contractions (n = 7) and mosaics (n = 1) detected by Southern blot were confirmed by molecular combing. Of the 71 samples with normal Southern blot results, 67 (94%) had concordant molecular combing results. The four discrepancies were either mosaic (n = 2), rearranged (n = 1), or borderline by molecular combing (n = 1). All indeterminate Southern blot results (n = 6) were resolved by molecular combing as either normal (n = 4), borderline (n = 1), or rearranged (n = 1). The two borderline Southern blot results showed a D4Z4 contraction on the chr 4qA allele and a normal result by molecular combing. Molecular combing overcomes a number of technical limitations of Southern blot by providing direct visualization of D4Z4 macrosatellite repeat arrays on specific chr 4q and chr 10q alleles and more precise D4Z4 repeat sizing. This study suggests that molecular combing has superior analytical validity compared to Southern blot for determining D4Z4 contraction size, detecting mosaicism, and resolving borderline and indeterminate Southern blot results. Further studies are needed to establish the clinical validity and diagnostic accuracy of these findings in FSHD., (Copyright © 2015 Elsevier B.V. All rights reserved.)

This brief review of current research progress on Charcot-Marie-Tooth (CMT) disease is a summary of discussions initiated at the Hereditary Neuropathy Foundation (HNF) scientific advisory board meeting on November 7, 2014. It covers recent published and unpublished in vitro and in vivo research. We discuss recent promising preclinical work for CMT1A, the development of new biomarkers, the characterization of different animal models, and the analysis of the frequency of gene mutations in patients with CMT. We also describe how progress in related fields may benefit CMT therapeutic development, including the potential of gene therapy and stem cell research. We also discuss the potential to assess and improve the quality of life of CMT patients. This summary of CMT research identifies some of the gaps which may have an impact on upcoming clinical trials. We provide some priorities for CMT research and areas which HNF can support. The goal of this review is to inform the scientific community about ongoing research and to avoid unnecessary overlap, while also highlighting areas ripe for further investigation. The general collaborative approach we have taken may be useful for other rare neurological diseases.

This study examines the neuropsychological profile of a boy with congenital central hypoventilation syndrome (CCHS) without a paired-like homeobox gene (PHOX2B) mutation. CCHS is a rare disorder of autonomic nervous system development characterized by an impaired ventilatory response to hypercarbia and hypoxemia. Mild intellectual deficits are common but a specific cognitive profile is not established in CCHS. We describe a nonverbal learning disorder as a CCHS endophenotype and recommend that detailed neuropsychological testing be performed on all individuals with CCHS. Defining the psycho-educational needs in CCHS may avert compounding the emotional and medical stresses of this already debilitating disorder.

A nonsense mutation (R419X) in the human cereblon gene [mutation (mut) CRBN] causes a mild type of autosomal recessive nonsyndromal mental retardation (ARNSMR). CRBN, a cytosolic protein, regulates the assembly and neuronal surface expression of large-conductance Ca(2+)-activated K(+) channels (BK(Ca)) in brain regions involved in memory and learning. Using the real-time quantitative polymerase chain reaction, we show that mut CRBN disturbs the development of adult brain BK(Ca) isoforms. These changes are predicted to result in BK(Ca) channels with a higher intracellular Ca(2+) sensitivity, faster activation, and slower deactivation kinetics. Such alterations may contribute to cognitive impairments in patients with mild ARNSMR.

Essential tremor (ET) is a movement disorder characterized by a postural or kinetic tremor of the hands, head, or voice. It is typically a familial condition and affects 1% to 4% of the general population. The trait is genetically linked to chromosome 2p in some families. A variant (828C-->G) in exon 7 of the hematopoietic-specific protein 1 binding protein 3 gene (HS1-BP3) on chromosome 2p recently has been found to segregate with ET in 2 families. To determine the frequency of this variant in a larger series, we studied patients with ET, Parkinson disease (PD), and controls without tremor. Affected singletons representing 73 families from the United States with dominantly inherited ET, 35 individuals with PD, and 304 healthy controls older than age 60 were tested for the 828C-->G variant in exon 7 of the HS1-BP3 gene by a BseYI restriction enzyme digest of the polymerase chain reaction product. Heterozygous carriers of the mutant allele were identified in 12 individuals with ET (16.4%) and in 1 individual with PD and postural tremor (3%). All of the healthy controls (608 chromosomes) were homozygous for the wild-type allele. The 828C-->G genetic variant in the HS1-BP3 gene occurs relatively frequently in subjects with ET. The variant may also be found in some individuals with PD and postural tremor. The HS1-BP3 gene plays a putative role in regulating catecholamine and serotonin metabolism, but the functional consequences of the amino acid substitution (A265G) caused by this genetic variant is unknown., ((c) 2005 Movement Disorder Society.)

The objective of this study was to analyze a sample of unrelated individuals with autosomal dominant essential tremor (ET) for a genetic association with loci in a candidate region (ETM2) on chromosome 2p24.1 that harbors a disease gene for ET. ET is a common movement disorder that is genetically linked to ETM2 in four large families. It is unknown whether this candidate locus is associated with dominantly inherited ET in other individuals. Based on information from previous genetic linkage studies, a linkage disequilibrium study was designed to compare individuals with a family history of ET (n=45) with normal controls (n=70). Three unreported dinucleotide polymorphic loci (etm1240, etm1231, and etm1234) were identified on a physical map of the ETM2 interval in a region of no recombination. The study sample was tested for allele frequency differences by the CLUMP program and haplotypes were analyzed by the FASTEHPLUS program. The allele frequencies were significantly different between ET cases and the control samples for the loci etm1231 (P< or =0.0419) and etm1234 (P<0.0001). A haplotype formed by the loci etm1231 and etm1234 occurred with a frequency of 29% in cases (n=45) and 9% in a white newborn sample (P<0.0001, n=35). The haplotype was not found in normal individuals older than 60 years without tremor (P=0.0063, n=35). This study provides evidence that an ancestral haplotype on chromosome 2p24.1 segregates with the ET disease phenotype in individuals with a family history of the disorder and will facilitate the search for a causative gene.