A fertile male patient with Kallmann syndrome and two missense mutations in the KAL1 gene.

OBJECTIVE: To present clinical, genetic, biochemical, and molecular findings in a male fertile patient with Kallmann syndrome (KS).
DESIGN: Case report.
SETTING: University medical center. PATIENT(S): A 26-year-old Chinese man. INTERVENTION(S): Clinical evaluation, hormone assays, gene mutation research. MAIN OUTCOME MEASURE(S): Endocrinologic evaluation and genetic analysis. RESULT(S): The patient had KS as a result of two missense mutations at exon 11 of KAL1 gene, 1690 G>A and 1765 G>A, a G→A transition in codons 514 and 539, which resulted in the replacement of lysine by glutamic acid, respectively. One of them is a novel mutation. CONCLUSION(S): Although loss-of-function mutations of the KAL1 gene is associated with the X-linked form of KS, the reproductive capacity remains unidentified in patients with KS with KAL1 gene mutations. Here, we report a male patient who presented the KS phenotype with fertility. The patient's sperm parameters were lower than the reference ranges; however, a son was born through natural conception after 12 months of marriage. Mutation analysis revealed two KAL1 gene mutations. The results provided further support for the hypothesis that patients with KS can achieve normal sexual development and fertility after hCG treatment, and imply that this genotype is more prevalent in reproductive patients with KS than in the other patients with KS and incurable infertility.