{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T20:23:04Z","timestamp":1783714984767,"version":"3.55.0"},"reference-count":33,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,12,18]],"date-time":"2020-12-18T00:00:00Z","timestamp":1608249600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100008397","name":"Velux Fonden","doi-asserted-by":"publisher","award":["32700"],"award-info":[{"award-number":["32700"]}],"id":[{"id":"10.13039\/100008397","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Bi-allelic pathogenic variants in MERTK cause retinitis pigmentosa (RP). Since deletions of more than one exon have been reported repeatedly for MERTK, CNV (copy number variation) analysis of next-generation sequencing (NGS) data has proven important in molecular genetic diagnostics of MERTK. CNV analysis was performed on NGS data of 677 individuals with inherited retinal diseases (IRD) and confirmed by quantitative RT-PCR analysis. Clinical evaluation was based on retrospective records. Clinical re-examination included visual field examination, dark adaption, scotopic and photopic full-field electroretinograms (ffERG), multifocal ERG (mfERG) and optic coherence tomography (OCT). Fourteen variants were detected in MERTK in six individuals, three of which were deletions of more than one exon. Clinical examinations of five out of six individuals revealed a severe phenotype with early-onset generalized retinal dystrophy with night blindness and progressive visual field loss; however, one individual had a milder phenotype. Three individuals had hearing impairments. We show that deletions represent a substantial part of the causative variants in MERTK and emphasize that CNV analysis should be included in the molecular genetic diagnostics of IRDs.<\/jats:p>","DOI":"10.3390\/genes11121517","type":"journal-article","created":{"date-parts":[[2020,12,21]],"date-time":"2020-12-21T04:12:01Z","timestamp":1608523921000},"page":"1517","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Bi-Allelic Pathogenic Variations in MERTK Including Deletions Are Associated with an Early Onset Progressive Form of Retinitis Pigmentosa"],"prefix":"10.3390","volume":"11","author":[{"given":"Cathrine","family":"Jespersgaard","sequence":"first","affiliation":[{"name":"Kennedy Center, Department of Clinical Genetics, Rigshospitalet, University of Copenhagen, 2600 Glostrup, Denmark"},{"name":"Danish National Genome Center, 2300 Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mette","family":"Bertelsen","sequence":"additional","affiliation":[{"name":"Kennedy Center, Department of Clinical Genetics, Rigshospitalet, University of Copenhagen, 2600 Glostrup, Denmark"},{"name":"Department of Ophthalmology, Rigshospitalet-Glostrup, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Farah","family":"Arif","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Rigshospitalet-Glostrup, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helene Gry","family":"Gellert-Kristensen","sequence":"additional","affiliation":[{"name":"Kennedy Center, Department of Clinical Genetics, Rigshospitalet, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mingyan","family":"Fang","sequence":"additional","affiliation":[{"name":"BGI-Shenzhen, Shenzhen 518083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hanne","family":"Jensen","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Rigshospitalet-Glostrup, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Rosenberg","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Rigshospitalet-Glostrup, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zeynep","family":"T\u00fcmer","sequence":"additional","affiliation":[{"name":"Kennedy Center, Department of Clinical Genetics, Rigshospitalet, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9524-4301","authenticated-orcid":false,"given":"Lisbeth Birk","family":"M\u00f8ller","sequence":"additional","affiliation":[{"name":"Kennedy Center, Department of Clinical Genetics, Rigshospitalet, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Br\u00f8ndum-Nielsen","sequence":"additional","affiliation":[{"name":"Kennedy Center, Department of Clinical Genetics, Rigshospitalet, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Gr\u00f8nskov","sequence":"additional","affiliation":[{"name":"Kennedy Center, Department of Clinical Genetics, Rigshospitalet, University of Copenhagen, 2600 Glostrup, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1604","DOI":"10.1126\/science.8202715","article-title":"Digenic retinitis pigmentosa due to mutations at the unlinked peripherin\/RDS and ROM1 loci","volume":"264","author":"Kajiwara","year":"1994","journal-title":"Science"},{"key":"ref_2","first-page":"139","article-title":"Retinal dystrophies, genomic applications in diagnosis and prospects for therapy","volume":"4","author":"Nash","year":"2015","journal-title":"Transl. 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