RESUMEN
Abstract Cystic fibrosis (CF) is an autosomal recessive disorder and is caused by variants in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. We aimed to study the frequency of the F508del variant, the most common variant worldwide, in patients with CF from Paraguay. The frequency of the F508del variant in Paraguayan patients with a clinical diagnosis of CF was assessed using a polymerase chain reaction followed by the sequencing of the PCR products. 43 of the 86 patients (50%) were homozygous for the F508del variant, 28 were heterozygous (32.56%), and the remaining 15 (17.44%) were non-carriers. In terms of alleles, there were 114 mutated (114/172 or 66.28%) and 58 did not correspond to this variant (58/172 or 33.72%). This is the first study of the frequency of the F508del variant in patients with CF in Paraguay. This information is of utmost relevance when planning and offering treatments from health services.