BACKGROUND: The spectrum and frequencies of CFTR mutations causing Cystic fibrosis (CF) varies among different populations in Europe, and beyond. METHODS: We identified 98.9% of all CFTR mutations in a representative cohort of 140 CF patients comprising 107 Bulgarian- (BG), 17 BG Turk-, and 16 BG Roma cases. The compiled clinical and genotype dataset includes 110 previously analyzed patients with 30 cases currently analyzed for rare CFTR variants by massively parallel sequencing of the entire CFTR coding region and adjacent introns combined with the analysis of intra-CFTR rearrangements. RESULTS: Altogether 53 different mutations, of which 15 newly identified in the BG CF population, were observed. Comparison of clinical and laboratory data between individual BG ethnic groups proved that BG Roma have a more severe nutritional status and are younger than other CF patients, as well as that the spectrum mutations differs between them. CONCLUSION: This collaborative study improves genetic counselling in BG, facilitates introduction of multitier CF neonatal screening and fosters public health measures for improvement of care in the Roma CF population.

Department of Biology and Medical Genetics University Hospital Motol Prague Czech Republic

Faculty of Medicine of Charles University Prague Czech Republic

Medical University Sofia Sofia Bulgaria

Pediatric Clinic University Hospital Alexandrovska Sofia Bulgaria

Pediatric Department Medical University Sofia Sofia Bulgaria

University Specialized Hospital for Active Treatment in Obstetrics and Gynecology 'Maichin dom' National Genetic Laboratory Sofia Bulgaria

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