A standardized approach to test missense PNPLA1 rare genetic variants of uncertain significance in epidermal differentiation disorders
Year: 2025
Type: article
Abstract: Congenital ichthyoses, now renamed Epidermal Differentiation Disorders (syndromic, sEDD or nonsyndromic, nEDD) are rare, disabling conditions caused by sequence variations in epidermal barrier genes. However, 5–10% of variants, called "Variants of Uncertain Significance" (VUS), remain uncharacterized and their pathogenicity not demonstrated. We developed an approach for classifying VUS in nEDD associated with variant in PNPLA1 . We generated PNPLA1 knockout (KO) human keratinocytes. PNPLA1, encoded by a missense VUS or by the reference coding sequence, was expressed following lentiviral transduction in the PNPLA1 KO cells. Transduced cells were used to produce human epidermal equivalents (HEEs) and the functionality of the normal or VUS-encoded proteins was evaluated. Compared to PNPLA1 KO-HEEs re-expressing normal PNPLA1, PNPLA1 KO-HEEs showed disrupted synthesis of ω-O-acylceramide, the normal product of PNPLA1, as well as abnormal vesicle-like structures and immature cornified envelopes, characteristic of PNPLA1 -mutated patients ‘epidermis. HEEs expressing the PNPLA1 VUS showed similar abnormalities, consistent with an impaired PNPLA1 function. This work demonstrated a feasible strategy to help reclassifying missense VUS, which can be extended to other EDD-related genes. Whereas further efforts are needed to translate this approach into clinical practice and help overcome current diagnostic limitations, such models are valuable tools for pathophysiological and preclinical research on EDDs.
Source: JID Innovations
Authors: Nuria Pell, Pauline Bernard, Séverine Courrech, Lukas Opalka, Aina Millán-Sánchez, Elise Levy, Séverine Garnier, Cyrielle Clément, Pauline Le Faouder, Katerina Vávrová, Olga López, Justine Bertrand-Michel, Corinne Leprince, Isabelle Fourquaux, José-Enrique Mejia, Jean-Christophe Pagès, Juliette Mazereeuw-Hautier, Nathalie Jonca
Institutions: Centre National de la Recherche Scientifique, Inserm, Hôpital Purpan, Institut Toulousain des Maladies Infectieuses et Inflammatoires, Université de Toulouse, Centre Hospitalier Universitaire de Toulouse, Charles University, Consejo Superior de Investigaciones Científicas, Institute of Advanced Chemistry of Catalonia, MetaboHUB, Institut des Maladies Métaboliques et Cardiovasculaires, École Nationale Vétérinaire de Toulouse, RESTORE
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,000
Funders: Fondation Maladies Rares, EuroNanoMed III, European Commission, European Cooperation in Science and Technology, Agence Nationale de la Recherche, Institut National de la Santé et de la Recherche Médicale, Ministerio de Economía y Competitividad, Ministerio de Ciencia e Innovación, Universitat de Barcelona, Société Française de Dermatologie et de Pathologie Sexuellement Transmissible, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Instituto de Salud Carlos III
Awards: G1190173965, Next generation metabolomics and fluxomics, from population to single cells, Pre-clinical development of an acylceramide nanostructured delivery system to rescue the skin barrier in patients with ichthyosis, G381665449, G4137996893, G4527245947, G473311507, G5281352633, G5802621812, G6396871349, G6776410370, G6898666373, G7240651115, MetaboHUB National Infrastructure of metabolomics and fluxomics, Caracterización y modulación de las células T de memoria residentes CD8+ para el control y eliminación de los reservorios virales, G883562873, Développement d'une infrastructure française distribuée pour la métabolomique dédiée à l'innovation
OpenAlex ID: W4417290668