Familial inheritance of crossed fused renal ectopia

A family with dominant inheritance of a rare renal malformation is reported . The father and one son had left crossed fused ectopic and dysplastic kidn eys and another son had a horseshoe kidney and vesicoureteral reflux. We di scuss various potential pathogenetic mechanisms and propose that a defect i n the timing of the proper reciprocal induction of the ureteric bud and the metanephric blastema is involved.