Ravnik-Glavac et al. (23) screened 80 men with idiopathic azoospermia, 50 men with severe oligozoospermia, 70 men with oligoasthenoteratozoospermia, and 7 men with CBAVD as well as 95 controls from Slovenia for mutations in 10 CFTR exons where the majority of the common CF disease causing mutations have been detected. This evidence concerns the gene CFTR and cystic fibrosis.