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We investigated the phenotypes and genotypes of a cohort of 'long-surviving' individuals with motor neuron disease (MND) to identify potential targets for prognostication.Patients were recruited via the Clinical Audit Research and Evaluation for MND (CARE-MND) platform, which hosts the Scottish MND Register. Long survival was defined as 8 years from diagnosis. 11 phenotypic variables were analysed. Whole genome sequencing (WGS) was performed and variants within 49 MND-associated genes examined. Each individual was screened for C9orf72 repeat expansions. Data from ancestry-matched Scottish populations (the Lothian Birth Cohorts) were used as controls.58 long survivors were identified. Median survival from diagnosis was 15.5 years. Long survivors were significantly younger at onset and diagnosis than incident patients and had a significantly longer diagnostic delay. 42% had the MND subtype of primary lateral sclerosis (PLS). WGS was performed in 46 individuals: 14 (30.4%) had a potentially pathogenic variant. 4 carried the known SOD1 p.(Ile114Thr) variant. Significant variants in FIG4, hnRNPA2B1, SETX, SQSTM1, TAF15, and VAPB were detected. 2 individuals had a variant in the SPAST gene suggesting phenotypic overlap with hereditary spastic paraplegia (HSP). No long survivors had pathogenic C9orf72 repeat expansions.Long survivors are characterised by younger age at onset, increased prevalence of PLS and longer diagnostic delay. Genetic analysis in this cohort has improved our understanding of the phenotypes associated with the SOD1 variant p.(Ile114Thr). Our findings confirm that pathogenic expansion of C9orf72 is likely a poor prognostic marker. Genetic screening using targeted MND and/or HSP panels should be considered in those with long survival, or early-onset slowly progressive disease, to improve diagnostic accuracy and aid prognostication.

BACKGROUND AND PURPOSE This study was undertaken to determine the prevalence of multimorbidity in people with motor neuron disease (MND) and to identify whether specific patterns of multimorbidity impact survival beyond age alone. METHODS We performed a retrospective analysis of the Scottish national MND register from 1 January 2015 to 29 October 2019. People with amyotrophic lateral sclerosis, primary lateral sclerosis, progressive muscular atrophy, or progressive bulbar palsy were included. We fitted latent class regression models incorporating comorbidities (class indicators), age, sex, and bulbar onset (covariates), and survival (distal outcome) with multimorbidity as a hypothesised latent variable. We also investigated the association between the Charlson Comorbidity Index and survival in Cox regression and compared its discrimination and calibration to age alone. RESULTS A total of 937 people with MND were identified (median age = 67 years, 60.2% male); 64.8% (n = 515) had two or more comorbidities. We identified a subpopulation with high prevalence of cardiovascular disease, but when accounting for the relationship between age and individual comorbidities, there was no difference in survival. Both Charlson Comorbidity Index (hazard ratio [HR] per unit increase = 1.11, 95% confidence interval [CI] = 1.07-1.15, p

Background and ObjectivesUnderstanding risk factors and spatial variation of risk may provide insights into the pathological mechanism of motor neuron disease (MND). Socioeconomic status (SES) has been hypothesised as a risk factor, but results from previous studies are inconsistent. No spatial epidemiology studies examining geographic clustering of MND have been performed in Scotland to date. We investigated the effect of SES and geography on MND risk in Scotland using the highly curated and nationally representative Scottish MND Register (CARE-MND) that has over 95% case ascertainment.MethodsPatients on the Scottish Clinical Audit Research Evaluation for Motor Neurone Disease platform, with date of diagnosis between 01 Jan 2015 and 28 Feb 2021 were included and geocoded with data zones using their residence at diagnosis. Indirectly standardised incidence ratio (SIR) accounting for age and sex was calculated for each health board. Poisson regression was used to examine the effect of SES on MND risk, adjusted for age and sex of population at risk. Geographic clustering was assessed using global Moran’s Index, Bayesian conditional autoregressive models and SaTScan software.ResultsAmong 1149 patients included, 1126 (98%) were successfully geocoded. Significantly lower SIR was shown in Highland (0.60, 95% CI 0.44 – 0.80, pp=0.008). However, risk maps using Bayesian modelling showed a relatively homogeneous distribution without distinct patterns across Scotland. Similarly, SaTScan did not detect any significant cluster of high or low risks.DiscussionOur findings support the notion that MND risk is mostly random-distributed and independent of SES in Scotland. Our results are generalizable to other MND populations.

Zebrafish exhibit robust regeneration following spinal cord injury, promoted by macrophages that control post-injury inflammation. However, the mechanistic basis of how macrophages regulate regeneration is poorly understood. To address this gap in understanding, we conducted a rapid in vivo phenotypic screen for macrophage-related genes that promote regeneration after spinal injury. We used acute injection of synthetic RNA Oligo CRISPR guide RNAs (sCrRNAs) that were pre-screened for high activity in vivo. Pre-screening of over 350 sCrRNAs allowed us to rapidly identify highly active sCrRNAs (up to half, abbreviated as haCRs) and to effectively target 30 potentially macrophage-related genes. Disruption of 10 of these genes impaired axonal regeneration following spinal cord injury. We selected 5 genes for further analysis and generated stable mutants using haCRs. Four of these mutants (tgfb1a, tgfb3, tnfa, sparc) retained the acute haCR phenotype, validating the approach. Mechanistically, tgfb1a haCR-injected and stable mutant zebrafish fail to resolve post-injury inflammation, indicated by prolonged presence of neutrophils and increased levels of il1b expression. Inhibition of Il-1β rescues the impaired axon regeneration in the tgfb1a mutant. Hence, our rapid and scalable screening approach has identified functional regulators of spinal cord regeneration, but can be applied to any biological function of interest., Author summary Nerve connections that are severed in spinal cord injury do not heal, which can lead to permanent paralysis. Lack of repair may in part be due to prolonged inflammation of the injury site. In contrast, zebrafish show excellent repair of nerve connections after spinal injury and this is associated with controlling inflammation. Due to recent advances in genetic technology (CRISPR/Cas9) we can now determine the function of genes that influence regeneration in the living zebrafish in a matter of days. Here we devise a very rapid screening method for the function of inflammation-related genes in zebrafish larvae after spinal cord injury. We find a number of genes that are necessary for repair of nerve connections and control of the inflammation after injury. This provides important leads to improve our understanding of the role of inflammation in spinal cord injury. Moreover, our fast and robust screening method can be adopted by other researchers to screen for gene functions in a whole animal, which was previously not easily possible.

Acute CRISPR/Cas9 targeting offers the opportunity for scalable phenotypic genetic screening in zebrafish. However, the unpredictable efficiency of CRISPR gRNA (CrRNA) activity is a limiting factor. Here we describe how to resolve this by prescreening CrRNAs for high activity in vivo, using a simple standardised assay based on restriction fragment length polymorphism analysis (RFLP). We targeted 350 genomic sites with synthetic RNA Oligo guide RNAs (sCrRNAs) in zebrafish embryos and found that almost half exhibited > 90% efficiency in our RFLP assay. Having the ability to preselect highly active sCrRNAs (haCRs), we carried out a focussed phenotypic screen of 30 macrophage-related genes in spinal cord regeneration and found 10 genes whose disruption impaired axonal regeneration. Four (tgfb1a, tgfb3, tnfa, sparc) out of 5 stable mutants subsequently analysed retained the acute haCR phenotype, validating the efficiency of this approach. Mechanistically, lack of tgfb1a leads to a prolonged immune response after injury, which inhibits regeneration. Our rapid and scalable screening approach has identified functional regulators of spinal cord regeneration, and can be applied to study any biological function of interest.HIGHLIGHTS- Synthetic CRISPR gRNAs are highly active- in vivo pre-screening allows rapid assessment of CRISPR gRNA activity- Phenotypic CRISPR screen reveals crucial genes for spinal cord regeneration- tgfb1a promotes spinal regeneration by controlling inflammation

Ten monoclonal antibodies and one lectin were used to study the localization and distribution of Blood Group ABH, type 1 chain (Lewis a, Lewis b) and type 2 chain (H-2, Y) antigens in 22 cases of normal uterine cervix, with known ABO and Lewis phenotype and secretor status. The results showed that ABH isoantigen expression is clearly related to the secretor status. It is positive in the endo- and exocervical epithelium of secretor individuals and negative in non-secretors. Lewis antigen expression in both endocervical and exocervical epithelium is related to the patient's Lewis phenotype and is clearly controlled by the secretor gene. Indeed, the expression of the Lewis a antigen is limited to the tissue of people of Lewis (a + b-) phenotype (non-secretors), and the expression of Lewis b antigen is limited to the tissue of people of Lewis a-b+) phenotype (secretors). The Y antigen showed a focal expression in endocervical mucosa in all the cases, independently of secretor status or Lewis phenotype. The same pattern was observed for H-type 2 antigen, though only in secretor individuals.