{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:47:56Z","timestamp":1787028476873,"version":"build-2736575974"},"reference-count":31,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,4,6]],"date-time":"2022-04-06T00:00:00Z","timestamp":1649203200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Academy of Dermatology and Venereology","award":["PPRC-2018-50"],"award-info":[{"award-number":["PPRC-2018-50"]}]},{"DOI":"10.13039\/501100003130","name":"Research Foundation - Flanders","doi-asserted-by":"publisher","award":["G035620N"],"award-info":[{"award-number":["G035620N"]}],"id":[{"id":"10.13039\/501100003130","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Special Research Fund, Flanders of Ghent University","award":["01N04516C"],"award-info":[{"award-number":["01N04516C"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Mosaic RASopathies are a molecularly heterogeneous group of (neuro)cutaneous syndromes with high phenotypical variability. Postzygotic variants in KRAS have been described in oculoectodermal syndrome (OES), encephalocraniocutaneous lipomatosis (ECCL) and epidermal nevus syndrome (ENS). This study confirms the continuum of mosaic neurocutaneous RASopathies showing codon 146 KRAS variants in an individual with OES and, for the first time, in an individual with (isolated) epidermal nevus. The presence of a nevus psiloliparus in individuals with OES indicates that this finding is not specific for ECCL and highlights the phenotypical overlap between ECCL and OES. The presence of the somatic KRAS variant in the nevus psiloliparus resolves the underlying molecular etiology of this fatty-tissue nevus. In addition, this finding refutes the theory of non-allelic twin-spotting as an underlying hypothesis to explain the concurrent presence of two different mosaicisms in one individual. The identification of codon 146 KRAS variants in isolated epidermal nevus introduces a new hot spot for this condition, which is useful for increasing molecular genetic testing using targeted gene sequencing panels.<\/jats:p>","DOI":"10.3390\/ijms23074036","type":"journal-article","created":{"date-parts":[[2022,4,6]],"date-time":"2022-04-06T05:11:34Z","timestamp":1649221894000},"page":"4036","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Identification of Codon 146 KRAS Variants in Isolated Epidermal Nevus and Multiple Lesions in Oculoectodermal Syndrome: Confirmation of the Phenotypic Continuum of Mosaic RASopathies"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0231-6861","authenticated-orcid":false,"given":"Aude","family":"Beyens","sequence":"first","affiliation":[{"name":"Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium"},{"name":"Department of Biomolecular Medicine, Ghent University Hospital, 9000 Ghent, Belgium"},{"name":"Department of Dermatology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laure","family":"Dequeker","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, General Hospital Sint-Jan Brugge-Oostende, 8000 Bruges, Belgium"},{"name":"Department of Ophthalmology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0325-4060","authenticated-orcid":false,"given":"Hilde","family":"Brems","sequence":"additional","affiliation":[{"name":"Department of Human Genetics, University Hospital Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7262-3715","authenticated-orcid":false,"given":"Sandra","family":"Janssens","sequence":"additional","affiliation":[{"name":"Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium"},{"name":"Department of Biomolecular Medicine, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0914-2676","authenticated-orcid":false,"given":"Hannes","family":"Syryn","sequence":"additional","affiliation":[{"name":"Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium"},{"name":"Department of Biomolecular Medicine, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne","family":"D\u2019Hooghe","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, General Hospital Sint-Jan Brugge-Oostende, 8000 Bruges, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pascale","family":"De Paepe","sequence":"additional","affiliation":[{"name":"Department of Pathology, General Hospital Sint-Jan Brugge-Oostende, 8000 Bruges, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lieve","family":"Vanwalleghem","sequence":"additional","affiliation":[{"name":"Department of Pathology, General Hospital Sint-Jan Brugge-Oostende, 8000 Bruges, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annelies","family":"Stockman","sequence":"additional","affiliation":[{"name":"Department of Dermatology, General Hospital Delta Roeselare-Menen-Torhout, 8820 Torhout, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Vankwikelberge","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofie","family":"De Schepper","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marleen","family":"Goeteyn","sequence":"additional","affiliation":[{"name":"Department of Dermatology, General Hospital Sint-Jan Brugge-Oostende, 8000 Bruges, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patricia","family":"Delbeke","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, General Hospital Sint-Jan Brugge-Oostende, 8000 Bruges, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9743-4205","authenticated-orcid":false,"given":"Bert","family":"Callewaert","sequence":"additional","affiliation":[{"name":"Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium"},{"name":"Department of Biomolecular Medicine, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"43","DOI":"10.4161\/cc.23108","article-title":"Mosaic RASopathies","volume":"12","author":"Hafner","year":"2013","journal-title":"Cell Cycle"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"764","DOI":"10.1002\/ajmg.1320450620","article-title":"Provisionally unique syndrome of ocular and ectodermal defects in two unrelated boys","volume":"45","author":"Toriello","year":"1993","journal-title":"Am. 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