{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T15:51:22Z","timestamp":1761061882441,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,9,9]],"date-time":"2023-09-09T00:00:00Z","timestamp":1694217600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Cystic Fibrosis Foundation","award":["FFC #8\/2021","FFC #8\/2020-extension"],"award-info":[{"award-number":["FFC #8\/2021","FFC #8\/2020-extension"]}]},{"name":"Italian Pasteur Institute","award":["FFC #8\/2021","FFC #8\/2020-extension"],"award-info":[{"award-number":["FFC #8\/2021","FFC #8\/2020-extension"]}]},{"name":"Cenci Bolognetti Foundation","award":["FFC #8\/2021","FFC #8\/2020-extension"],"award-info":[{"award-number":["FFC #8\/2021","FFC #8\/2020-extension"]}]},{"name":"Sapienza University of Rome","award":["FFC #8\/2021","FFC #8\/2020-extension"],"award-info":[{"award-number":["FFC #8\/2021","FFC #8\/2020-extension"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>In the precision medicine era of cystic fibrosis (CF), therapeutic interventions, by the so-called modulators, target the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The levels of targetable CFTR proteins are a main variable in the success of patient-specific therapy. In turn, the CFTR protein level depends, at least in part, on the level of CFTR mRNA. Many mechanisms can modulate the CFTR mRNA level, for example, transcriptional rate, stability of the mRNA, epigenetics, and pathogenic variants that can affect mRNA production and degradation. Independently from the causes of variable CFTR mRNA levels, their exact quantitative assessment is of great importance in CF. Methods with high analytical sensitivity, precision, and accuracy are mandatory for the quantitative evaluation aimed at the amelioration of the diagnostic, prognostic, and therapeutic aspects. This paper compares, for the first time, two CFTR gene expression quantification methods: a well-established method for the relative quantification of CFTR mRNA using a real-time PCR and an innovative method for its absolute quantification using a droplet digital PCR. No comprehensive methods for absolute CFTR quantification via droplet digital PCR have been published so far. The accurate quantification of CFTR expression at the mRNA level is a critical step for the personalized therapeutic approaches of CF.<\/jats:p>","DOI":"10.3390\/genes14091781","type":"journal-article","created":{"date-parts":[[2023,9,11]],"date-time":"2023-09-11T09:00:52Z","timestamp":1694422852000},"page":"1781","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Quantitative Evaluation of CFTR Gene Expression: A Comparison between Relative Quantification by Real-Time PCR and Absolute Quantification by Droplet Digital PCR"],"prefix":"10.3390","volume":"14","author":[{"given":"Sabina Maria","family":"Bruno","sequence":"first","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1955-820X","authenticated-orcid":false,"given":"Giovanna","family":"Blacon\u00e0","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefania","family":"Lo Cicero","sequence":"additional","affiliation":[{"name":"Department of Oncology and Molecular Medicine, National Institute of Health, Istituto Superiore di Sanit\u00e0, ISS, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3593-1230","authenticated-orcid":false,"given":"Germana","family":"Castelli","sequence":"additional","affiliation":[{"name":"Department of Oncology and Molecular Medicine, National Institute of Health, Istituto Superiore di Sanit\u00e0, ISS, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mariarita","family":"Virgulti","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giancarlo","family":"Testino","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silvia","family":"Pierandrei","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9467-5671","authenticated-orcid":false,"given":"Andrea","family":"Fuso","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giuseppe","family":"Cimino","sequence":"additional","affiliation":[{"name":"Cystic Fibrosis Reference Center of Lazio Region, Policlinico Umberto I University Hospital, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6129-4071","authenticated-orcid":false,"given":"Giampiero","family":"Ferraguti","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adriana","family":"Eramo","sequence":"additional","affiliation":[{"name":"Department of Oncology and Molecular Medicine, National Institute of Health, Istituto Superiore di Sanit\u00e0, ISS, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5538-2494","authenticated-orcid":false,"given":"Marco","family":"Lucarelli","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1480","DOI":"10.1378\/chest.10-2077","article-title":"Cystic fibrosis transmembrane conductance regulator intracellular processing, trafficking, and opportunities for mutation-specific treatment","volume":"139","author":"Rogan","year":"2011","journal-title":"Chest"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/S1569-1993(01)00003-0","article-title":"The cystic fibrosis transmembrane conductance regulator: An intriguing protein with pleiotropic functions","volume":"1","author":"Vankeerberghen","year":"2002","journal-title":"J. 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