The phenotype of renal agenesis/dysgenesis strongly indicates the existence of KAL1 gene defects in the genotype of patients with sporadic KS, providing evidence for the X-linked mode of inheritance and offering the opportunity for genetic counseling.
A defective anosmin-1 molecule may also play a role in the development of synkinesia and renal agenesis, which are exclusively seen in the X-linked form of KS.
The high frequency of renal agenesis in this family, in the presence and absence of the KAL-1 mutation, suggests an autosomal dominant or X-linked gene which may independently or co-dependently contribute to renal agenesis.
In addition, the high frequency of unilateral renal aplasia in X-linked Kallmann patients (6 out of 11 males with identified alterations of the KAL gene) should be emphasized.