Mutations in CFTR genes are associated with oligoasthenospermia in infertile men undergoing IVF

Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation has been clearly defined in congenital absence of the vas deferens (CAVD), which is an important cause of obstructive azoospermia. However, the association between oligoasthenospermia and CFTR gene mutation remains controversial. To confirm this issue, 151 infertile Chinese men were screened for CFTR mutation by NGS approach, including 18 CAVD patients, 72 patients with severe oligoasthenospermia and 61 controls with normal sperm parameters. Frequency of mutation in exons of CFTR gene were 66.7% in CAVD patients (12/18) (p < 0.001) and 8.33% in severe oligoasthenospermic patients (6/72) (p < 0.05), both of which were significantly more frequent than that in the controls (0/61). In terms of introns mutation of CFTR gene, there was no significant difference in frequency of 5T between oligoasthenospermic men (5/144, 3.47%) and the controls (4/122, 3.28%) (p = 0.645). In addition, 6 novel mutations in exons of CFTR gene in this study (c.3736A>G, c.635T>G, c.482delA, c.1858C>T, c.2042A>T, c.1586A>C) have not been reported in the Cystic Fibrosis Mutation Database before. Thus, our study provides evidence that CFTR gene mutation may be the aetiology of severe oligoasthenospermia other than CAVD. It may be necessary to screen for CFTR mutations in men with severe oligoasthenospermia before receiving assisted reproductive technology.