{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T09:50:53Z","timestamp":1775555453045,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T00:00:00Z","timestamp":1775433600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Epigenomes"],"abstract":"<jats:p>Background: Parental imprinting plays a crucial role in epigenetic regulation and is increasingly recognized for its involvement in neurodevelopmental disorders. Although ATP8A2 is considered a non-imprinted gene; However, the marked phenotypic variability observed across related disorders suggests that additional regulatory layers may influence its expression. Methods: We investigated the imprinting-like status of ATP8A2 through functional analyses of a splicing variant (c.1580-3C&gt;G) identified in a patient diagnosed with Cerebellar Ataxia, Mental Retardation, and Disequilibrium syndrome type 4 (CAMRQ4). Sanger sequencing was used to assess allelic expression and identify aberrant transcripts. Results: Our analyses revealed an allelic expression imbalance suggestive of parental imprinting of ATP8A2. Moreover, Sanger sequencing led to the identification of a novel ATP8A2\u2013RAB3GAP2 chimeric transcript, pointing to a previously unreported transcriptional event, the functional relevance of which remains to be determined. Conclusions: These findings indicate that ATP8A2 may be subject to imprinting-like regulation and involved in atypical splicing events with unknown significance. This highlights the need for further investigation into the epigenetic and transcriptional complexity of ATP8A2-related neurodevelopmental disorders.<\/jats:p>","DOI":"10.3390\/epigenomes10020026","type":"journal-article","created":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T08:09:00Z","timestamp":1775549340000},"page":"26","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Novel Perspectives on ATP8A2 Regulation: Evidence for Parental Imprinting and Chimeric Transcript Formation"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-3618-5396","authenticated-orcid":false,"given":"Abdelhamid","family":"Bouramtane","sequence":"first","affiliation":[{"name":"Medical Genetics & Oncogenetics Laboratory, Hassan II University Hospital Center, Sidi Harazem Road, Fez 30070, Morocco"},{"name":"Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5312-8612","authenticated-orcid":false,"given":"Badreddine","family":"Elmakhzen","sequence":"additional","affiliation":[{"name":"Medical Genetics & Oncogenetics Laboratory, Hassan II University Hospital Center, Sidi Harazem Road, Fez 30070, Morocco"},{"name":"Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amal","family":"Ouskri","sequence":"additional","affiliation":[{"name":"Medical Genetics & Oncogenetics Laboratory, Hassan II University Hospital Center, Sidi Harazem Road, Fez 30070, Morocco"},{"name":"Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohamed","family":"Ahakoud","sequence":"additional","affiliation":[{"name":"Medical Genetics & Oncogenetics Laboratory, Hassan II University Hospital Center, Sidi Harazem Road, Fez 30070, Morocco"},{"name":"Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laila","family":"Bouguenouch","sequence":"additional","affiliation":[{"name":"Medical Genetics & Oncogenetics Laboratory, Hassan II University Hospital Center, Sidi Harazem Road, Fez 30070, Morocco"},{"name":"Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karim","family":"Ouldim","sequence":"additional","affiliation":[{"name":"Medical Genetics & Oncogenetics Laboratory, Hassan II University Hospital Center, Sidi Harazem Road, Fez 30070, Morocco"},{"name":"Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Omar","family":"Askander","sequence":"additional","affiliation":[{"name":"Mohammed VI Center for Research and Innovation CM6RI, Rabat 10112, Morocco"},{"name":"Mohammed VI Faculty of Medicine, Mohammed VI University of Health Sciences, Rabat 10112, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1038\/35047554","article-title":"Genomic imprinting: Parental influence on the genome","volume":"2","author":"Reik","year":"2001","journal-title":"Nat. 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