{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:19:29Z","timestamp":1792790369808,"version":"4.5.0"},"posted":{"date-parts":[[2026,9,28]]},"group-title":"Genetic and Genomic Medicine","reference-count":22,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T00:00:00Z","timestamp":1790553600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Medical Research Council","award":["MR\/Z504725\/1"],"award-info":[{"award-number":["MR\/Z504725\/1"]}]},{"name":"National Institute of Mental Health","award":["R01MH129751"],"award-info":[{"award-number":["R01MH129751"]}]},{"award":["305292\/Z\/23\/Z"],"award-info":[{"award-number":["305292\/Z\/23\/Z"]}],"id":[{"id":"https:\/\/ror.org\/029chgv08","id-type":"ROR","asserted-by":"publisher"}]},{"id":[{"id":"https:\/\/ror.org\/03356n642","id-type":"ROR","asserted-by":"publisher"}]},{"name":"NHMRC","award":["2041062"],"award-info":[{"award-number":["2041062"]}],"id":[{"id":"https:\/\/ror.org\/011kf5r70","id-type":"ROR","asserted-by":"crossref"}]},{"award":["09150172110002"],"award-info":[{"award-number":["09150172110002"]}],"id":[{"id":"https:\/\/ror.org\/01bnjb948","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Sophia Research Foundation"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,9,29]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>\n                  ReNU syndrome is a severe neurodevelopmental disorder caused by\n                  <jats:italic>de novo<\/jats:italic>\n                  variants in the spliceosomal small nuclear RNA (snRNA) gene\n                  <jats:italic>RNU4-2.<\/jats:italic>\n                  Pathogenic variants cluster in two distinct structural regions of the U4 snRNA produced by\n                  <jats:italic>RNU4-2<\/jats:italic>\n                  , the T-loop and Stem III. Aberrant 5\u2019 splice site selection is a molecular hallmark of ReNU syndrome that correlates with phenotypic severity and could be leveraged as a quantitative biomarker to facilitate preclinical and clinical therapeutic development. We analysed RNA-sequencing data from two independent cohorts totalling 30 individuals with ReNU syndrome and 54 controls. We identified 483 alternative splicing events shared across both cohorts, with the highest concordance in 105 alternative 5\u2019 splice-site (A5SS) events. Using these 105 A5SS events, we derived a minimal reproducible signature from only six sites. The splicing signature perfectly distinguished 19 n.64_65insT individuals from 54 controls, and produced no false positives when applied to a further 5,984 whole blood controls. In addition, the signature was specific to variants within the U4-2 T-loop, which are associated with greater clinical severity. Further, we find evidence of alternative splicing events that are specific to variants in Stem III. In a patient-derived induced pluripotent stem cell (iPSC) model of the recurrent\n                  <jats:italic>RNU4-2<\/jats:italic>\n                  n.64_64insT variant, the splicing signature was fully recapitulated across all stages of differentiation into cortical neuron-like cells. Together, these findings define a robust RNA biomarker for T-loop ReNU syndrome for use in therapeutic development, and illustrate a general framework for portable biomarker discovery in spliceopathies.\n                <\/jats:p>","DOI":"10.64898\/2026.09.26.26364077","type":"posted-content","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T20:45:21Z","timestamp":1790628321000},"source":"Crossref","is-referenced-by-count":0,"title":["A cross-tissue splicing signature as a quantitative biomarker for ReNU syndrome"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2135-0117","authenticated-orcid":false,"given":"Ruebena","family":"Dawes","sequence":"first","affiliation":[{"name":"Big Data Institute, University of Oxford, Oxford, UK"},{"name":"Centre for Human Genetics, University of Oxford, Oxford, UK"},{"name":"Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford, OX3 7TY, UK"},{"name":"Garvan Institute of Medical Research, and UNSW Sydney, Sydney, NSW, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0260-7020","authenticated-orcid":false,"given":"Alexander","family":"Blakes","sequence":"additional","affiliation":[{"name":"Big Data Institute, University of Oxford, Oxford, UK"},{"name":"Centre for Human Genetics, University of Oxford, Oxford, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0115-264X","authenticated-orcid":false,"given":"Theodora","family":"Markati","sequence":"additional","affiliation":[{"name":"Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford, OX3 7TY, UK"},{"name":"John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Headley Way, Headington, Oxford, Oxfordshire, OX3 9DU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Griffiths","sequence":"additional","affiliation":[{"name":"Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford, OX3 7TY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5503-6292","authenticated-orcid":false,"given":"Benjamin","family":"Cogn\u00e9","sequence":"additional","affiliation":[{"name":"Nantes Universit\u00e9, CHU de Nantes, CNRS, INSERM, L\u2019Institut du Thorax, Nantes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1231-1562","authenticated-orcid":false,"given":"Tahsin Stefan","family":"Barakat","sequence":"additional","affiliation":[{"name":"Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, 3000 CA, Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1152-370X","authenticated-orcid":false,"given":"Jeffrey C","family":"Barrett","sequence":"additional","affiliation":[{"name":"ELLIS Institute Finland, Helsinki, Finland"},{"name":"Institute for Molecular Medicine Finland (FIMM), HiLIFE, University of Helsinki, Finland"},{"name":"Faculty of Medicine, University of Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8307-6638","authenticated-orcid":false,"given":"Carlo","family":"Rinaldi","sequence":"additional","affiliation":[{"name":"Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford, OX3 7TY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9112-5148","authenticated-orcid":false,"given":"Stephan J","family":"Sanders","sequence":"additional","affiliation":[{"name":"Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford, OX3 7TY, UK"},{"name":"Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA 94158, USA"},{"name":"New York Genome Center, New York, NY 10013, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1554-6594","authenticated-orcid":false,"given":"Nicola","family":"Whiffin","sequence":"additional","affiliation":[{"name":"Big Data Institute, University of Oxford, Oxford, UK"},{"name":"Centre for Human Genetics, University of Oxford, Oxford, 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