Reference genes for circadian profiling of core clock genes in the blood of obstructive sleep apnea patients

Nahtigal, Katarina (avtor), Halužan Vasle, Ana (avtor), Kreft, Tinkara (avtor), Skubic, Cene (avtor), Mraz, Miha (avtor), Moškon, Miha (avtor), Dolenc-Grošelj, Leja (avtor), Rozman, Damjana (avtor)

Circadian rhythm disruptions are increasingly recognized in disorders such as obstructive sleep apnea (OSA), yet analysis of 24 h gene expression patterns remains challenging due to the lack of reliable reference genes for normalization. Even commonly used housekeeping genes may exhibit circadian oscillations, which can confound rhythmic gene expression analyses and hinder biomarker identification. To address this limitation, we evaluated the gene expression stability of 11 commonly used housekeeping genes in blood collected every 6 h over 24 h period from 40 adults with varying OSA severity and controls. Stability ranking by analytical tools RefFinder and EndoGeneAnalyzer identified ACTB (β-actin) and RPL13A (ribosomal protein L13a) as the most consistent reference genes, with minimal intra- and inter-individual variability across sampling times and disease groups. Their suitability was assessed by personalized cosinor analysis of core clock genes (BMAL1, PER2, CRY1), demonstrating that appropriate normalization enables detection of circadian oscillations in clinical samples. Using the optimal normalization, CosinorPy analysis of the core clock genes revealed significant circadian oscillations of at least one clock gene in the studied participants. These findings establish ACTB and RPL13A as robust reference genes for blood-based circadian studies of OSA and provide an important methodological framework for future circadian biomarker research.

• Jezik: Angleški jezik
• Ključne besede: circadian rhythms, obstructive sleep apnea, reference genes, qRT-PCR normalization, gene expression stability, core clock genes
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: MF - Medicinska fakulteta
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2026
• Št. strani: 18 str.
• Številčenje: Vol. 16, iss. 7, art. 1013
• PID: 20.500.12556/RUL-184903
• UDK: 577.2
• ISSN pri članku: 2218-273X
• DOI: 10.3390/biom16071013
• COBISS.SI-ID: 285115907
• Datum objave v RUL: 17.07.2026

Gradivo je del revije

• Naslov: Biomolecules
• Skrajšan naslov: Biomolecules
• Založnik: MDPI
• ISSN: 2218-273X
• COBISS.SI-ID: 519952921

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: cirkadiani ritmi, obstruktivna apneja v spanju, referenčni geni, normalizacija qRT-PCR, stabilnost izražanja genov, osrednji geni uravnavanja ritma, ključni geni biološke ure