PT - JOURNAL ARTICLE AU - Stojka Fustik AU - Dijana Plaseska Karanfilska AU - Marija Terzikj AU - Lidija Spirevska AU - Ana Stamatova TI - Spectrum of CFTR mutations in Republic of North Macedonia AID - 10.1183/13993003.congress-2020.2768 DP - 2020 Sep 07 TA - European Respiratory Journal PG - 2768 VI - 56 IP - suppl 64 4099 - http://erj.ersjournals.com/content/56/suppl_64/2768.short 4100 - http://erj.ersjournals.com/content/56/suppl_64/2768.full SO - Eur Respir J2020 Sep 07; 56 AB - Introduction: The incidence of cystic fibrosis (CF) and the spectrum of CFTR mutations varies considerably between populations and regions of the world. Balkan region is known for greater heterogeneity, attributed to a long history of population migration in these countries from the Middle East and Europe.Aims and Objectives: The aim of the study was to analyze the genotype of CF patients treated at our clinic for the last 10 years (since entering data in ECSPR) and the prevalence of CTRT mutations in our country.Methods: The diagnosis of CF was made on the basis of clinical and laboratory criteria, included positive sweat test and/or presence of two CF-causing mutations. Initially, patients were screened using SNaPshot reaction for the 11 most common CF mutations. Additional CF mutations and large deletions/duplications in the CFTR gene were analyzed using commercial kits. When the genotype was undetermined, all CFTR exons were analyzed using Sanger DNA sequencing or next generation sequencing. Newborn screening (NBS) for CF was introduced in the country in 2019.Results: Proportion of identified mutations was 99.6%.The most common CFTR mutation F508del was found with an overall incidence of 72.3%. Other mutations with more significant incidence were: G542X (5.3%), N1303K (1.9%), G1349D (1.9%), G126D (1.9%),V456F (1.5%) and 621+1G>T (1.5%). Additionally, 24 other CFTR pathogenic variants, including four large deletions were identified.Two of these were novel.Conclusion: CFTR analysis showed that despite the predominance of a number of mutations, R.N. Macedonia has one of the most diverse mutational profiles in Europe. NBS revealed much high incidence of the disease in Albanian population compared toMacedonian.FootnotesCite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 2768.This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).