Heterogeneity of reproductive tract abnormalities in men with absence of the vas deferens: role of cystic fibrosis transmembrane conductance regulator gene mutations.

To determine if the types of reproductive tract abnormalities linked to absence of the vas deferens varies with the cystic fibrosis transmembrane conductance regulator (CFTR) genotype. Prospective data gathering. University infertility clinic. Forty-six infertile men with absence of the scrotal vas deferens and no signs of cystic fibrosis. All had blood taken for CFTR gene analysis, 33 had scrotal ultrasounds, and 25 had transrectal ultrasounds. The frequency of testicular, seminal vesicle, and ampullae of the vas deferens malformations was compared between subgroups of men with two, one, or no CFTR gene mutations. None (0 of 21) of the men with at least one CFTR gene mutations had normal ampullae of the vas or seminal vesicles bilaterally. Two (50%) of 4 men with no CFTR gene mutations had normal ampullae of the vas deferens bilaterally, and 50% had normal bilateral seminal vesicles (statistically significantly different). There was no correlation between testicular malformations and CFTR genotype. This study indicates that the severity of the malformations in the testis is unrelated to the CFTR genotype, whereas the frequency and severity of wolffian duct malformations are related directly to the CFTR genotype.