Background: Why some individuals experience severe neuropathy following infection is unknown. Nucleocytoplasmic trafficking (NCT) is an essential process in nucleated cells, and its disruption has been implicated in many neurodegenerative conditions including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Methods: We performed genomic and clinical studies in 24 individuals from 12 families with acute onset axonal neuropathy. Genetic variants were characterized by thermal stability and enzymatic assays using recombinantly expressed protein. Protein localization was determined in patient fibroblasts using immunofluorescence following heat or oxidative stress. A humanized Drosophila model was generated to determine the effect of stress on in vivo function. Results: We identified deleterious biallelic variants in human RCC1, encoding a GTP exchange factor essential in maintaining Ran GTPase-dependent NCT function. Clinical presentations ranged from a rapidly progressive, fatal axonal neuropathy with encephalopathy to a mild motor neuropathy resulting in impaired walking. In most patients (n=22/24), neurological presentation was secondary to infection, resulting in prior diagnosis of Guillain-Barre syndrome (GBS) in 13. The efficiency of cellular Ran GDP-GTP exchange and the thermal stability of Rcc1 protein was reduced by disease-associated variants. Heat shock or oxidative stress revealed defects in Ran nuclear localization, impaired NCT, and TDP-43 mislocalization in patient fibroblasts. Disease associated variants were unable to rescue the thermosensitive phenotype of a rcc1 deficient hamster cell line. RCC1 Drosophila models revealed a fatal intolerance to oxidative stress. Conclusion: We describe a novel autosomal recessive acute onset axonal neuropathy triggered by infection caused by biallelic RCC1 variants, which mimics GBS and has important mechanistic overlap with ALS. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement We acknowledge grant support from: the Wellcome Trust ; the Manchester NIHR BRC (NIHR203308); LifeArc Pathfinder award; and NIHR Doctoral Fellow, 301748). This research was made possible through access to data in the National Genomic Research Library, which is managed by Genomics England Limited (a wholly owned company of the Department of Health and Social Care). The National Genomic Research Library holds data provided by patients and collected by the NHS as part of their care and data collected as part of their participation in research. The National Genomic Research Library is funded by the National Institute for Health Research and NHS England. The Wellcome Trust, Cancer Research UK and the Medical Research Council have also funded research infrastructure. Further acknowledgements of funding are provided in the supplementary appendix. A.B. is supported by a Wellcome PhD Training Fellowship for Clinicians and the 4Ward North PhD Programme for Health Professionals (223521/Z/21/Z). P.L. is supported by Ministry of Health of the Czech Republic, grant. no: NW24-04-00349. R.H. is supported by the Wellcome Discovery Award (226653/Z/22/Z), the Medical Research Council (UK) (MR/V009346/1), the Addenbrookes Charitable Trust (G100142), the Hereditary Neuropathy Foundation, the Stoneygate Trust, the Lily Foundation, Ataxia UK, Action for AT, the Muscular Dystrophy UK, the LifeArc Centre to Treat Mitochondrial Diseases (LAC-TreatMito) and the UKRI/Horizon Europe Guarantee MSCA Doctoral Network Programme (Project 101120256: MMM). This research was supported by the NIHR Cambridge Biomedical Research Centre (BRC-1215-20014). The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care. H.L. receives support from the Canadian Institutes of Health Research (CIHR) for Foundation Grant FDN-167281 (Precision Health for Neuromuscular Diseases), Transnational Team Grant ERT-174211 (ProDGNE) and Network Grant OR2-189333 (NMD4C), from the Canada Foundation for Innovation (CFI-JELF 38412), the Canada Research Chairs program (Canada Research Chair in Neuromuscular Genomics and Health, 950-232279), the European Commission (Grant # 101080249) and the Canada Research Coordinating Committee New Frontiers in Research Fund (NFRFG-2022-00033) for SIMPATHIC, and from the Government of Canada Canada First Research Excellence Fund (CFREF) for the Brain-Heart Interconnectome (CFREF-2022-00007). RWT is funded by the Wellcome Centre for Mitochondrial Research (203105/Z/16/Z), the Mitochondrial Disease Patient Cohort (UK) (G0800674), the Medical Research Council (MR/W019027/1), the Lily Foundation, the Pathological Society, the UK NIHR Biomedical Research Centre for Ageing and Age-related disease award to the Newcastle upon Tyne Foundation Hospitals NHS Trust, LifeArc and the UK NHS Highly Specialised Service for Rare Mitochondrial Disorders of Adults and Children. R.D.S.P. is funded by The Lily Foundation, Muscular Dystrophy UK (MDUK), and a seedcorn award from the Rosetrees Trust and Stoneygate Foundation. R.D.S.P. is supported by a Medical Research Council (UK) Transition Support award (MR/X02363X/1), Medical Research Council (UK) award MC\_PC\_21046 to establish a National Mouse Genetics Network Mitochondria Cluster (MitoCluster), and the LifeArc Centre to Treat Mitochondrial Diseases (LAC-TreatMito). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Written informed consent was obtained from all persons in the study (or from their parents or guardians) in accordance with the Declaration of Helsinki protocols, and our experimental protocols were approved by the NHS institutional review board (IRAS 64321). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors

Genetic variants in ATP7A are associated with a spectrum of X-linked disorders. In descending order of severity, these are Menkes disease, occipital horn syndrome, and X-linked distal spinal muscular atrophy. After 30 years of diagnostic investigation, we identified a deep intronic ATP7A variant in four males from a family affected to variable degrees by a predominantly skeletal phenotype, featuring bowing of long bones, elbow joints with restricted mobility which dislocate frequently, coarse curly hair, chronic diarrhoea, and motor coordination difficulties. Analysis of whole genome sequencing data from the Genomics England 100,000 Genomes Project following clinical re-evaluation identified a deep intronic ATP7A variant, which was predicted by SpliceAI to have a modest splicing effect. Using a mini-gene splicing assay, we determined that the intronic variant results in aberrant splicing. Sanger sequencing of patient cDNA revealed ATP7A transcripts with exon 5 skipping, or inclusion of a novel intron 4 pseudoexon. In both instances, frameshift leading to premature termination are predicted. Quantification of ATP7A mRNA transcripts using a qPCR assay indicated that the majority of transcripts (86.1 %) have non-canonical splicing, with 68.0 % featuring exon 5 skipping, and 18.1 % featuring the novel pseudoexon. We suggest that the variability of the phenotypes within the affected males results from the stochastic effects of splicing. This deep intronic variant, resulting in aberrant ATP7A splicing, expands the understanding of intronic variation on the ATP7A-related disease spectrum.

Urorectal septum malformation sequence (URSMS) is characterized by a spectrum of anomalies of the urogenital system, hindgut and perineum. It is presumed to be a constellation of an embryonic defect. Herein, we analyzed the clinically diverse syndromes associated with URSMS in our perinatal evaluation unit. We reviewed fetuses with URSMS in referrals for perinatal autopsy over a period of 3 years. Chromosomal microarray and genome sequencing were performed whenever feasible. Literature was reviewed for syndromes or malformations with URSMS. We ascertained URSMS in 12 of the 215 (5%) fetuses. Nine fetuses (75%) had complete URSMS and remainder had partial/intermediate URSMS. Eleven fetuses had malformations of other systems that included: cerebral ventriculomegaly; right aortic arch with double outlet right ventricle; microcephaly with fetal akinesia deformation sequence; ventricular septal defect and radial ray anomaly; thoraco-abdominoschisis and limb defects; myelomeningocele; spina bifida and fused iliac bones; omphalocele; occipital encephalocele; lower limb amelia and cleft foot. We report on six fetuses with recurrent and five fetuses with unique malformations/patterns where URSMS is a component. Exome sequencing (one family) and genome sequencing (eight families) were performed and were nondiagnostic. Additionally, we review the literature for genetic basis of this condition. URMS is a clinically heterogeneous condition and is a component of several multiple malformation syndromes. We describe several unique and recurrent malformations associated with URSMS.

Introduction Bladder exstrophyeepispadias complex (BEEC) comprises a spectrum of anterior midline congenital malformations, involving the lower urinary tract. BEEC is usually sporadic, but families with more than one affected member have been reported, and a twin concordance study supported a genetic contribution to pathogenesis. Moreover, diverse chromosomal aberrations have been reported in a small subset of individuals with BEEC. The commonest are 22q11.2 microduplications, identified in approximately 3% of BEEC index cases. Objectives We aimed to refine the chromosome 22q11.2 locus, and to determine whether the encompassed genes are expressed in normal developing and mature human urinary bladders. Results Using DNA from an individual with CBE, the 22q11.2 duplicated locus was refined by identification of a maternally inherited 314 kb duplication (chr22:21,147,293e21,461,017), as depicted in this image. Moreover, the eight protein coding genes within the locus were found to be expressed during normal developing and mature bladders. To determine whether duplications in any of these individual genes were associated with CBE, we undertook copy number analyses in 115 individuals with CBE without duplications of the whole locus. No duplications of individual genes were found. Discussion The current study has refined the 22q11.2 locus associated with BEEC and has shown that the eight protein coding genes are expressed in human bladders both during antenatal development and postnatally. Nevertheless, the precise biological explanation as to why duplication of the phenocritical region of 22q11 confers increased susceptibility to BEEC remains to be determined. The fact that individuals with CBE without duplications of the whole locus also lacked duplication of any of the individual genes suggests that in individuals with BEEC and duplication of the 22q11.2 locus altered dosage of more than one gene may be important in BEEC etiology. Conclusions The study has refined the 22q11.2 locus associated with BEEC and has shown that the eight protein coding genes within this locus are expressed in human bladders.

Several decades ago, Bernardo Ochoa1 described a rare but potentially devastating inherited disease that is now called urofacial, or Ochoa, syndrome (UFS).2 UFS is characterized by 2 features. First, a so-called “non-neurogenic neurogenic” dyssynergic bladder in which functional bladder outflow obstruction causes incomplete voiding, vesicoureteric reflux (VUR), ascending urosepsis, pyelonephritis, and renal failure. Second, a grimace where the corners of the mouth become downturned on smiling, so that the face appears to be crying.