Fertile Eunuch Syndrome with the Mutations (Trp8Arg and Ile15Thr) in the β Subunit of Luteinizing Hormone

Abstract

Fertile eunuch syndrome is caused by isolated LH deficiency, but its pathophysiology still remains controversial. We report a case of fertile eunuch syndrome with homozygous Trp8Arg and Ile15Thr mutations in the LH β subunit gene. An 18-year-old man was admitted to our hospital for hypogonadism. Examination of genitalia revealed Tanner G1PH1, whereas both testes were elastically palpated and developed up to 18 ml. Endocrinological evaluations revealed normogonadotropic hypogonadism and there were normal responses after GnRH and hCG stimulation. Intratesticular testosterone concentration was almost normal (1.34 × 10³ ng/g). By PCR direct sequencing, homozygous Trp (8) Arg and Ile (15) Thr mutations in exon 2 of LH β were detected. Normal virilization and improved semen parameters were achieved after hCG supplementation. To our knowledge, this is the first case of fertile eunuch syndrome with homozygous Trp (8) Arg and Ile (15) Thr mutations in β subunit of LH gene.