Marissa et al. demonstrated that FGFR2 plays an important role in the normal development of the external genitalia and that knockdown of FGFR2 in endodermal cells resulted in hypospadias and inhibition of urethral epithelial maturation, while knockdown of FGFR2 in ectodermal cells resulted in severe hypospadias and absence of the ventral foreskin [15]. The gene discussed is FGFR2; the disease is hypospadias.