{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T10:46:08Z","timestamp":1776854768272,"version":"3.51.2"},"reference-count":43,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T00:00:00Z","timestamp":1776816000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000055","name":"NIDCD\/NIH","doi-asserted-by":"publisher","award":["R01DC016295"],"award-info":[{"award-number":["R01DC016295"]}],"id":[{"id":"10.13039\/100000055","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000055","name":"NIDCD\/NIH","doi-asserted-by":"publisher","award":["R01DC012564"],"award-info":[{"award-number":["R01DC012564"]}],"id":[{"id":"10.13039\/100000055","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Hearing loss (HL) is a common sensory disorder, with syndromic forms accounting for ~30% of genetic cases. Due to phenotypic and genetic heterogeneity, accurate diagnosis remains challenging. Exome sequencing (ES) offers a powerful tool to uncover the underlying genetic causes. This study aimed to investigate the genetic basis of syndromic hearing loss (SHL) in North African Moroccan patients through ES. Seven individuals with suspected SHL were recruited from Hassan II University Hospital, Fez. After clinical and audiological assessments, ES was performed to identify causal genetic variants. Two of the participating individuals had Usher syndrome, and one each had Cornelia de Lange syndrome, Wolfram syndrome, Jervell and Lange-Nielsen syndrome, CHARGE syndrome, and Waardenburg syndrome. The causes of all these syndromes were determined, with pathogenic variants in MYO7A, USH1G, SMC1A, WFS1, KCNQ1, CHD7, and MITF. Across the combined cohort of reported Moroccan SHL cases, variants in CHD7 and MYO7A were among the most frequently observed, while USH1G and MITF variants were rare. This study enhances the understanding of SHL in North Africa, revealing a high level of locus and allelic heterogeneity. Examining disparate populations yields novel insights into the etiology of SHL, which can subsequently enhance genetic diagnosis and tailored management strategies.<\/jats:p>","DOI":"10.3390\/biom16050619","type":"journal-article","created":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T09:01:24Z","timestamp":1776848484000},"page":"619","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular Characterization of Syndromic Hearing Loss in North African Moroccan Families"],"prefix":"10.3390","volume":"16","author":[{"given":"Khawla","family":"El Fizazi","sequence":"first","affiliation":[{"name":"Laboratory of Biomedical and Translational Research, Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"},{"name":"Unit of Medical Genetics and Oncogenetics, Hassan II University Hospital, Fez 30050, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amama","family":"Ghaffar","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head & Neck Surgery, University of Maryland, Baltimore, MD 21201, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laila","family":"Bouguenouch","sequence":"additional","affiliation":[{"name":"Laboratory of Biomedical and Translational Research, Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"},{"name":"Unit of Medical Genetics and Oncogenetics, Hassan II University Hospital, Fez 30050, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Irum Badshah","family":"Saleem","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head & Neck Surgery, University of Maryland, Baltimore, MD 21201, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karim","family":"Ouldim","sequence":"additional","affiliation":[{"name":"Laboratory of Biomedical and Translational Research, Faculty of Medicine, Pharmacy and Dentistry, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"},{"name":"Unit of Medical Genetics and Oncogenetics, Hassan II University Hospital, Fez 30050, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2914-4502","authenticated-orcid":false,"given":"Zubair M.","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head & Neck Surgery, University of Maryland, Baltimore, MD 21201, USA"},{"name":"Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, MD 21201, USA"},{"name":"Marlene & Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, MD 21201, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohammed","family":"Ridal","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Hassan II University Hospital, Fez 30050, Morocco"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Saima","family":"Riazuddin","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head & Neck Surgery, University of Maryland, Baltimore, MD 21201, USA"},{"name":"Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, MD 21201, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e76","DOI":"10.1002\/cpz1.76","article-title":"Congenital Deafness and Recent Advances towards Restoring Hearing Loss","volume":"1","author":"Renauld","year":"2021","journal-title":"Curr. 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