As a mitochondrial P450 system, P450c11 is dependent on two electron transfer proteins, adrenodoxin reductase and adrenodoxin that transfer 2 electrons from NADPH to the P450 for each monooxygenase reaction catalyzed by the enzyme. In most respects this process of electron transfer appears similar to that of P450scc system that catalyzes cholesterol side chain cleavage.  Similar to P450scc the process of electrons transfer is leaky leading to superoxide production. The rate of electron leakage during metabolism depends on the functional groups of the steroid substrate. 
Hardelin et al. (1993) reported results of a mutation search of the KAL1 gene in 21 unrelated males with familial Kallmann syndrome. In 2 families, large deletions that included the entire KAL gene were detected by Southern blot analysis. By sequencing each of the 14 coding exons and splice site junctions in the other 19 patients, they found 9 point mutations at separate locations in 4 exons and 1 splice site. They emphasized the high frequency of unilateral renal aplasia in X-linked Kallmann syndrome patients; 6 of 11 males with identified alterations of the KAL gene showed this feature.