CFTR and cystic fibrosis: In cystic fibrosis, an autosomal recessive genetic disease linked to a mutation in chromosome 7 of the gene encoding a protein that controls the chlorine channel (CFTR: Cystic Fibrosis Transmembrane Conductance Regulator), thick and viscous mucus is produced, involving several organs such as the lung, pancreas, and liver, and is also responsible for infertility [11].