{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"Research Square"}],"indexed":{"date-parts":[[2024,7,26]],"date-time":"2024-07-26T00:13:54Z","timestamp":1721952834517},"posted":{"date-parts":[[2024,4,19]]},"group-title":"In Review","reference-count":0,"publisher":"Springer Science and Business Media LLC","license":[{"start":{"date-parts":[[2024,4,19]],"date-time":"2024-04-19T00:00:00Z","timestamp":1713484800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2024,4,1]]},"abstract":"<title>Abstract<\/title>\n        <p>Spinocerebellar ataxias (SCA) are most frequently due to (CAG)n (coding for polyglutamine, polyQ) expansions and, less so, to expansion of other oligonucleotide repeats (non-polyQ) or other type of variants (non-repeat expansion SCA). In this study we compared polyQ and non-repeat expansion SCA, in a cohort of patients with hereditary ataxia followed at a tertiary hospital. From a prospective study, 88 patients (51 families) with SCA were selected, 74 (40 families) of whom genetically diagnosed.\nThirty-eight patients (51.4%, 19 families) were confirmed as having a polyQ (no other repeat-expansions were identified) and 36 (48.6%, 21 families) a non-repeat expansion SCA. Median age-at-onset was 39.5 [30.0-45.5] for polyQ and 7.0 years [1.00-21.50] for non-repeat expansion SCA. PolyQ SCA were associated with cerebellar onset, and non-repeat expansion forms with non-cerebellar onset. Time to diagnosis was longer for non-repeat expansion SCA. The most common polyQ SCA were Machado-Joseph disease (MJD\/SCA3) (73.7%) and SCA2 (15.8%); whereas in non-repeat expansion SCA ATX-CACNA1A (14.3%), ATP1A3-related ataxia, ATX-ITPR1, ATX\/HSP-KCNA2, and ATX-PRKCG (9.5% each) predominated. Disease duration (up to inclusion) was significantly higher in non-repeat expansion SCA, but the difference in SARA score was not statistically significant. Cerebellar peduncles and pons atrophy were more common in polyQ ataxias, as was axonal neuropathy.\nSCA had a wide range of genetic etiology, age-at-onset and presentation. Proportion of polyQ and non-repeat expansion SCA was similar; the latter had a higher genetic heterogeneity. While polyQ ataxias were typically linked to cerebellar onset in adulthood, non-repeat expansion forms associated with early onset and non-cerebellar presentations.<\/p>","DOI":"10.21203\/rs.3.rs-4200296\/v1","type":"posted-content","created":{"date-parts":[[2024,4,19]],"date-time":"2024-04-19T17:56:59Z","timestamp":1713549419000},"source":"Crossref","is-referenced-by-count":0,"title":["Spinocerebellar ataxias: phenotypic spectrum of polyQ versus non-repeat expansion forms"],"prefix":"10.21203","author":[{"given":"Jo\u00e3o","family":"Moura","sequence":"first","affiliation":[{"name":"Hospital de Santo Ant\u00f3nio, Unidade Local de Sa\u00fade de Santo Ant\u00f3nio (ULSSA)"}]},{"given":"Jorge","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Institute for Research and Innovation in Health"}]},{"given":"Mariana","family":"Santos","sequence":"additional","affiliation":[{"name":"Institute for Research and Innovation in Health"}]},{"given":"Sara","family":"Costa","sequence":"additional","affiliation":[{"name":"Hospital de Santo Ant\u00f3nio, Unidade Local de Sa\u00fade de Santo Ant\u00f3nio (ULSSA)"}]},{"given":"L\u00e9nia","family":"Silva","sequence":"additional","affiliation":[{"name":"Hospital de Santo Ant\u00f3nio, Unidade Local de Sa\u00fade de Santo Ant\u00f3nio (ULSSA)"}]},{"given":"Carolina","family":"Lemos","sequence":"additional","affiliation":[{"name":"Universidade do Porto"}]},{"given":"Jos\u00e9","family":"Barros","sequence":"additional","affiliation":[{"name":"Hospital de Santo Ant\u00f3nio, Unidade Local de Sa\u00fade de Santo Ant\u00f3nio (ULSSA)"}]},{"given":"Jorge","family":"Sequeiros","sequence":"additional","affiliation":[{"name":"Universidade do Porto"}]},{"given":"Joana","family":"Dam\u00e1sio","sequence":"additional","affiliation":[{"name":"Hospital de Santo Ant\u00f3nio, Unidade Local de Sa\u00fade de Santo Ant\u00f3nio (ULSSA)"}]}],"member":"297","container-title":[],"original-title":[],"link":[{"URL":"https:\/\/www.researchsquare.com\/article\/rs-4200296\/v1","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.researchsquare.com\/article\/rs-4200296\/v1.html","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,7,25]],"date-time":"2024-07-25T00:32:32Z","timestamp":1721867552000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.researchsquare.com\/article\/rs-4200296\/v1"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,4,19]]},"references-count":0,"URL":"https:\/\/doi.org\/10.21203\/rs.3.rs-4200296\/v1","relation":{"is-preprint-of":[{"id-type":"doi","id":"10.1007\/s12311-024-01723-9","asserted-by":"subject"}]},"subject":[],"published":{"date-parts":[[2024,4,19]]},"subtype":"preprint"}}