{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T14:48:15Z","timestamp":1783522095878,"version":"3.55.0"},"reference-count":27,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,6]],"date-time":"2024-08-06T00:00:00Z","timestamp":1722902400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Russian Science Foundation","award":["23-64-00002"],"award-info":[{"award-number":["23-64-00002"]}]},{"name":"Russian Science Foundation","award":["075-03-2023-106\/12"],"award-info":[{"award-number":["075-03-2023-106\/12"]}]},{"name":"Ministry of Science and Higher Education of the Russian Federation","award":["23-64-00002"],"award-info":[{"award-number":["23-64-00002"]}]},{"name":"Ministry of Science and Higher Education of the Russian Federation","award":["075-03-2023-106\/12"],"award-info":[{"award-number":["075-03-2023-106\/12"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: Cone dystrophy with supernormal rod response (CDSRR) is a rare autosomal recessive retinal disorder characterized by a delayed and markedly decreased photoreceptor response. In this article, we aim to describe the clinical course and associated molecular findings in children with cone dystrophy with supernormal rod response associated with recessive mutations in the KCNV2 gene, which encodes a subunit (Kv8.2) of the voltage-gated potassium channel. Methods: The genetic testing of two patients included the next-generation sequencing of a retinal dystrophy panel and direct Sanger sequencing to confirm KCNV2 gene variants, in addition to an electroretinogram (ERG) and spectral domain optical coherence tomography (SD-OCT). Results: Cone dystrophy with supernormal rod response is associated with identified variants in the KCNV2 gene. The genetic analysis of the first case identified a compound heterozygous mutation in the KCNV2 gene, including a de novo nonsense duplication at cDNA position 1109, which led to the premature termination of the p.Lys371Ter codon in the second extracellular domain of the protein. Two patients showed changes in the full-field electroretinogram, especially in the first case, which demonstrated a close to supernormal total electroretinogram amplitude. This study increased the range of the KCNV2 mutation database, added an unreported de novo substitution pattern to KCNV2 gene variants, and linked it to the evaluated clinical studies. Conclusions: The initial clinical manifestations were varied, but both patients presented with hypermetropia and slight exotropia. The ERG findings are characteristic of KCNV2 mutations, and patients exhibited an increased b-wave latency in DA3.0 ERG (combined rod\u2013cone response).<\/jats:p>","DOI":"10.3390\/jcm13164592","type":"journal-article","created":{"date-parts":[[2024,8,6]],"date-time":"2024-08-06T11:54:19Z","timestamp":1722945259000},"page":"4592","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Novel and Previously Known Mutations of the KCNV2 Gene Cause Various Variants of the Clinical Course of Cone Dystrophy with Supernormal Rod Response in Children"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9698-0634","authenticated-orcid":false,"given":"Almaqdad","family":"Alsalloum","sequence":"first","affiliation":[{"name":"Federal Research Center for Innovator and Emerging Biomedical and Pharmaceutical Technologies, 125315 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilya","family":"Mosin","sequence":"additional","affiliation":[{"name":"Pediatric City Clinical Hospital Named for Z.A. Bashlyaevoy, 129272 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0568-6593","authenticated-orcid":false,"given":"Kristina","family":"Shefer","sequence":"additional","affiliation":[{"name":"S. Fyodorov \u201cEye Microsurgery\u201d Federal State Institution St. Petersburg Branch, 192283 St. Petersburg, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-9967-8388","authenticated-orcid":false,"given":"Natalia","family":"Mingaleva","sequence":"additional","affiliation":[{"name":"Federal Research Center for Innovator and Emerging Biomedical and Pharmaceutical Technologies, 125315 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3636-1820","authenticated-orcid":false,"given":"Alexander","family":"Kim","sequence":"additional","affiliation":[{"name":"Federal Research Center for Innovator and Emerging Biomedical and Pharmaceutical Technologies, 125315 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofya","family":"Feoktistova","sequence":"additional","affiliation":[{"name":"Federal Research Center for Innovator and Emerging Biomedical and Pharmaceutical Technologies, 125315 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5666-3493","authenticated-orcid":false,"given":"Boris","family":"Malyugin","sequence":"additional","affiliation":[{"name":"S.N. Fedorov National Ophthalmology Medical Research Center \u201cEye Microsurgery\u201d, 127486 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ernest","family":"Boiko","sequence":"additional","affiliation":[{"name":"S. Fyodorov \u201cEye Microsurgery\u201d Federal State Institution St. Petersburg Branch, 192283 St. Petersburg, Russia"},{"name":"North-Western State Medical University Named after I.I. Mechnikov, 191015 St. Petersburg, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shamil","family":"Sultanov","sequence":"additional","affiliation":[{"name":"Artema Therapeutics Inc., Brooklyn, NY 11201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olga","family":"Mityaeva","sequence":"additional","affiliation":[{"name":"Federal Research Center for Innovator and Emerging Biomedical and Pharmaceutical Technologies, 125315 Moscow, Russia"},{"name":"Department of Fundamental Medicine, Lomonosov Moscow State University, 119992 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9794-6297","authenticated-orcid":false,"given":"Pavel","family":"Volchkov","sequence":"additional","affiliation":[{"name":"Federal Research Center for Innovator and Emerging Biomedical and Pharmaceutical Technologies, 125315 Moscow, Russia"},{"name":"Department of Fundamental Medicine, Lomonosov Moscow State University, 119992 Moscow, Russia"},{"name":"Moscow Clinical Scientific Center N.A. A.S. Loginov, 111123 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"574","DOI":"10.1086\/507568","article-title":"Mutations in the gene KCNV2 encoding a voltage-gated potassium channel subunit cause \u201ccone dystrophy with supernormal rod electroretinogram\u201d in humans","volume":"79","author":"Wu","year":"2006","journal-title":"Am. J. Hum. Genet."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"751","DOI":"10.1167\/iovs.07-0471","article-title":"Cone dystrophy with supernormal rod response is strictly associated with mutations in KCNV2","volume":"49","author":"Wissinger","year":"2008","journal-title":"Investig. Ophthalmol. Vis. 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