Unilateral renal agenesis associated with congenital bilateral absence of the vas deferens: phenotypic findings and genetic considerations

An association between congenital bilateral absence of the vas deferens (CB AVD), normal renal anatomy and cystic fibrosis (CF) gene mutations is well established (CF/CBAVD). We postulate that unilateral renal agenesis (URA) a nd CBAVD (URA/CBAVD) may have a non-CF mutation-mediated genetic basis that leads to abnormal development of the entire mesonephric duct at a very ear ly stage in embryo development (less than or equal to7 weeks). The physical , laboratory and radiographic findings of men with URA/CBAVD (n = 17) and C F/CBAVD (n = 97) were compared; the fertilization and pregnancy rates in th e URA/CBAVD population calculated, and the incidence of renal agenesis in i mmediate family members and offspring of men with URA/CBAVD analysed. No st atistical differences could be identified within any of the above compariso ns. The fertilization rate for the URA/CBAVD group was 58.2 +/- 26.3%. Eigh t infants and two fetuses had normal renal anatomy, while one terminated ma le fetus had bilateral renal and vasal agenesis. Thirty first-order relativ es had normal renal units. Anatomical expression of the reproductive ductal derivatives in men with URA/CBAVD and CF/CBAVD was similar, but the phenot ypic outcome of the renal portion of the mesonephric duct was different. Th e potential for transmission of this fatal anomaly reinforces the need for prenatal ultrasounds with all pregnancies involving URA/CBAVD men.