*Result*: Large variations in total and allele-specific transcript expression in a disease mutation-independent manner.

Title:
Large variations in total and allele-specific transcript expression in a disease mutation-independent manner.
Authors:
Freyberg M; Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany., Bewig M; Faculty of Medicine, Saarland University, Homburg, Germany., Bampi GB; Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany., Manfredi C; Department of Pediatrics, School of Medicine, Emory University, Atlanta, USA.; Children's Healthcare of Atlanta, Atlanta, USA., Joshi D; Department of Pediatrics, School of Medicine, Emory University, Atlanta, USA.; Children's Healthcare of Atlanta, Atlanta, USA., Rauscher R; Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany., Hong JS; Department of Pediatrics, School of Medicine, Emory University, Atlanta, USA.; Children's Healthcare of Atlanta, Atlanta, USA., Große-Onnebrink J; Münster University Hospital, Münster, Germany., Sutharsan S; Department of Pulmonary Medicine, Division of Cystic Fibrosis, University Medicine Essen-Ruhrlandklinik, University of Duisburg-Essen, Essen, Germany., Stehling F; Pediatric Pulmonology University Hospital of Essen, Essen, Germany., Bobis I; Christiane Herzog Zentrum Nord, Städtisches Krankenhaus Kiel, Kiel, Germany., Ballmann M; Pediatric and Adolescence Clinic, University Medicine Rostock, Rostock, Germany. Manfred.Ballmann@med.uni-rostock.de., Sorscher EJ; Department of Pediatrics, School of Medicine, Emory University, Atlanta, USA. esorscher@emory.edu.; Children's Healthcare of Atlanta, Atlanta, USA. esorscher@emory.edu., Ignatova Z; Institute of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany. zoya.ignatova@uni-hamburg.de.
Source:
Scientific reports [Sci Rep] 2026 Feb 27; Vol. 16 (1). Date of Electronic Publication: 2026 Feb 27.
Publication Type:
Journal Article
Language:
English
Journal Info:
Publisher: Nature Publishing Group Country of Publication: England NLM ID: 101563288 Publication Model: Electronic Cited Medium: Internet ISSN: 2045-2322 (Electronic) Linking ISSN: 20452322 NLM ISO Abbreviation: Sci Rep Subsets: MEDLINE; In Process
Imprint Name(s):
Original Publication: London : Nature Publishing Group, copyright 2011-
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Contributed Indexing:
Keywords: Allele skewing; Cystic fibrosis; Gene expression; Monogenic diseases; mRNA
Entry Date(s):
Date Created: 20260227 Latest Revision: 20260302
Update Code:
20260303
DOI:
10.1038/s41598-026-40624-1
PMID:
41760671
Database:
MEDLINE

*Further Information*

*Individuals with monogenic diseases, even those with identical disease-causing mutations, exhibit considerable clinical heterogeneity in severity and outcomes. In this study, we quantified total and allele-specific transcript levels in nasal brushings from patients diagnosed with cystic fibrosis (CF) who are homozygous or compound heterozygous for variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Among CF patients, total CFTR transcript levels showed greater variability than in non-CF individuals, although both groups exhibited a broad range of transcript expression. Compound heterozygous study subjects also displayed notable differences in allelic dosage, known as allelic skewing. The expression from the non-F508del allele predominated in the total transcript pool. For a small group of patients with nasal brushings available before and after treatment with FDA/EMA-approved drugs Trikafta/Kaftrio (a combination of elexacaftor-tezacaftor-ivacaftor) or Symkevi (a combination of tezacaftor-ivacaftor), we observed no effect on total CFTR transcript abundance but detected changes in allelic expression patterns. These findings reveal important aspects to be considered for personalized therapeutic approaches to CF and other monogenic diseases and emphasize previously unappreciated aspects of mRNA expression during pathogenesis.
(© 2026. The Author(s).)*

*Declarations. Competing interests: The authors declare no competing interests. Ethical approval and consent to participate: This is a multicenter study approved by the Ethical Review Board of the University of Rostock (registration number: A 2016-0077). Informed consent for nasal brushings was obtained from each participant or the participant’s parent (if the participant was a minor) and archived locally, at the participating clinics.*