Wolffian duct anomalies [editorial].

The fact that a serum factor in cystic fibrosis patients inhibits ciliary 
movement of cells of isolated tracheae, and the observation that ciliary 
movement is associated with pinocytotic activity led Ohno et al. to 
suggest that this defect is responsible for aplasia or hypoplasia of 
the wolffian duct structures in males with cystic fibrosis. While Ohno's 
hypothesis lacks definitive proof, the hypoplasia or aplasia of the vas 
in males with cystic fibrosis is extremely common, producing sterility in 
affected males. 