PROKR2 mutations and SPRY4 variants with uncertain significance in a Kallmann syndrome family: Incomplete penetrance.

Kallmann syndrome is a rare genetic disease characterized by the idiopathic hypogonadotropic hypogonadism with hyposmia or anosmia, which exhibits considerable heterogeneity in genotype and phenotype. Herein, we reported a 32-year-old male patient with Kallmann syndrome in a family associated with heterozygous mutations in PROKR2 and SPRY4 genes. The genotyping results indicated PROKR2 mutations and SPRY4 variants of uncertain significance, which might be incompletely penetrant in this family.