{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T10:49:55Z","timestamp":1785408595241,"version":"3.56.0"},"reference-count":21,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T00:00:00Z","timestamp":1782172800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["PMPER2400022"],"award-info":[{"award-number":["PMPER2400022"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]},{"award":["PMPER2400022"],"award-info":[{"award-number":["PMPER2400022"]}],"id":[{"id":"https:\/\/ror.org\/00ca2c886","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Fondo Europeo de Desarrollo Regional (FEDER) funds"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background and Clinical Significance: Biallelic pathogenic variants in the PCARE gene (photoreceptor cilium actin regulator), also known as C2orf71 (chromosome 2 open reading frame 71), are typically associated with retinitis pigmentosa type 54 (RP54) and, less frequently, with cone\u2013rod dystrophy (CORD23). Case Presentation: A 52-year-old man presented with an eight-year history of progressive visual loss, without photophobia or nyctalopia. He underwent a comprehensive ophthalmological evaluation, including multimodal retinal imaging, automated perimetry, and full electrophysiological testing, in accordance with International Society for Clinical Electrophysiology of Vision (ISCEV)\u2019s standards. Genetic testing was performed using next-generation sequencing (NGS) with an inherited retinal dystrophy gene panel, and findings were confirmed by Sanger sequencing. Clinical examination revealed bilateral macular atrophy with minimal foveal sparing and a central scotoma. Optical coherence tomography (OCT) showed disruption of the outer retinal layers and retinal pigment epithelium (RPE) abnormalities. Fundus autofluorescence (FAF) demonstrated central hypoautofluorescence surrounded by a hyperautofluorescent ring. Electrophysiological testing revealed severely reduced rod- and cone- mediated responses on full-field electroretinography (ERG), absent pattern ERG responses, and markedly reduced multifocal ERG responses, indicating widespread retinal dysfunction with significant macular involvement. Genetic analysis identified a homozygous pathogenic nonsense variant in PCARE [c.3289C&gt;T; p.(Gln1097*)], confirming the diagnosis of an autosomal recessive inherited retinal dystrophy. Conclusions: Biallelic PCARE variants can cause late-onset severe retinal dystrophy, with predominant macular involvement and cone\u2013rod dysfunction. Given its phenotypic overlap with other inherited retinal diseases, accurate diagnosis requires the integration of multimodal retinal imaging, electrophysiological testing, and comprehensive genetic analysis.<\/jats:p>","DOI":"10.3390\/diagnostics16131945","type":"journal-article","created":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T08:19:52Z","timestamp":1782202792000},"page":"1945","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Cone\u2013Rod Dystrophy PCARE-Associated Retinopathy"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6184-5718","authenticated-orcid":false,"given":"Maria","family":"Sopena-Pinilla","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Hospital Universitario Miguel Servet, 50009 Zaragoza, Spain"},{"name":"Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Arruebo-Mu\u00f1io","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Hospital Cl\u00ednico Universitario Lozano Blesa, 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-4756-8362","authenticated-orcid":false,"given":"Marta","family":"Arias-Alvarez","sequence":"additional","affiliation":[{"name":"Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain"},{"name":"Department of Neurophysiology, Hospital Cl\u00ednico Universitario Lozano Blesa, 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-7694-8086","authenticated-orcid":false,"given":"Maria","family":"Arcas-Carbonell","sequence":"additional","affiliation":[{"name":"Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-9557-4903","authenticated-orcid":false,"given":"Pablo","family":"Tejada-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain"},{"name":"Department of Ophthalmology, Hospital Cl\u00ednico Universitario Lozano Blesa, 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carmen","family":"Lahuerta-Pueyo","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Hospital Cl\u00ednico Universitario Lozano Blesa, 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diana","family":"P\u00e9rez Garc\u00eda","sequence":"additional","affiliation":[{"name":"Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain"},{"name":"Department of Ophthalmology, Hospital Cl\u00ednico Universitario Lozano Blesa, 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0349-9997","authenticated-orcid":false,"given":"Isabel","family":"Pinilla","sequence":"additional","affiliation":[{"name":"Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain"},{"name":"Department of Ophthalmology, Hospital Cl\u00ednico Universitario Lozano Blesa, 50009 Zaragoza, Spain"},{"name":"Department of Surgery, University of Zaragoza, 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zufiaurre-Seijo, M., Garc\u00eda-Arum\u00ed, J., and Duarri, A. 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