{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T23:53:54Z","timestamp":1789430034693,"version":"build-2803163510"},"reference-count":37,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,11]],"date-time":"2023-09-11T00:00:00Z","timestamp":1694390400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Ichthyoses are genetically determined cornification disorders of the epidermis characterized by the presence of different degrees of scaling, hyperkeratosis, and erythroderma often associated with palmoplantar keratoderma. Different classifications of these diseases have been proposed, often based upon the involved genes and\/or the clinical presentation. The clinical features of these diseases present some overlap of phenotypes among distinct genetic entities, depending mainly on the penetrance of mutations. In this study, using a clinical, genetic, and molecular approach, we analyzed a family with two affected members who had clinical and histological features resembling erythrokeratodermia variabilis (EKV) or a type of erythrodermic hyperkeratosis with palmoplantar keratoderma. Despite of the clinical presentation, we demonstrated that the affected patients were genetically double heterozygous for two different mutations in the ABCA12 gene, known to be responsible for harlequin ichthyosis. To explain the mild phenotype of our patients, we performed a molecular characterization of the skin. In the upper layers of the epidermis, the results showed a patchy presence of the glucosyl-ceramides (GlcCer), which is the lipid transported by ABCA12, fundamental in contributing to skin impermeability. Indeed, the two mutations detected do not completely abolish ABCA12 activity, indicating that the mild phenotype is due to a partial loss of function of the enzyme, thus giving rise to an intermediate phenotype resembling EKVP, due to a partial depletion of GlcCer deposition.<\/jats:p>","DOI":"10.3390\/ijms241813962","type":"journal-article","created":{"date-parts":[[2023,9,12]],"date-time":"2023-09-12T04:38:48Z","timestamp":1694493528000},"page":"13962","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Partial Loss of Function ABCA12 Mutations Generate Reduced Deposition of Glucosyl-Ceramide, Leading to Patchy Ichthyosis and Erythrodermia Resembling Erythrokeratodermia Variabilis et Progressiva (EKVP)"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7442-2252","authenticated-orcid":false,"given":"Alessandro","family":"Terrinoni","sequence":"first","affiliation":[{"name":"Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriele","family":"Sala","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ernesto","family":"Bruno","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences and Translational Medicine University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9148-667X","authenticated-orcid":false,"given":"Consuelo","family":"Pitolli","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2512-4793","authenticated-orcid":false,"given":"Marilena","family":"Minieri","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3463-0268","authenticated-orcid":false,"given":"Massimo","family":"Pieri","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandra","family":"Gambacurta","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Campione","sequence":"additional","affiliation":[{"name":"Department of System Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-2465-9235","authenticated-orcid":false,"given":"Riccardo","family":"Belardi","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sergio","family":"Bernardini","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"186","DOI":"10.2340\/00015555-3432","article-title":"Genetics of Inherited Ichthyoses and Related Diseases","volume":"100","author":"Fischer","year":"2020","journal-title":"Acta Derm. -Venereol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"adv00095","DOI":"10.2340\/00015555-3431","article-title":"Molecular Genetics of Keratinization Disorders\u2014What\u2019s New About Ichthyosis","volume":"100","author":"Uitto","year":"2020","journal-title":"Acta Derm. -Venereol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"442","DOI":"10.1111\/j.1365-2133.2010.10096.x","article-title":"Expanding the keratin mutation database: Novel and recurrent mutations and genotype-phenotype correlations in 28 patients with epidermolytic ichthyosis","volume":"164","author":"Arin","year":"2011","journal-title":"Br. 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