Bronchiectasis with or without elevated sweat chloride-2 (BESC2, OMIM:613021) is caused by mutation in the gene encoding the α-subunit of ENaC (SCNN1A), and bronchiectasis with or without elevated sweat chloride-3 (BESC3, OMIM:613071) is caused by mutation in the gene encoding the γ-subunit (SCNN1G). The gene discussed is SCNN1A; the disease is bronchiectasis.