Low basal testosterone and impaired testosterone response to human chorionic gonadotrophin (hCG) stimulation were observed in a patient with NR5A1 mutation (c.103-3CO A/WT) born with a micropenis, scrotal hypospadias and bilateral inguinal gonads with the presence of a vaginal rest as a rudimentary Mullerian structure. Here, NR5A1 is linked to Micropenis.