CYP19 and ESR2 polymorphisms as potential culprits in cryptorchidism.

Introduction: Cryptorchidism impairs sperm development and increases the risk of infertility and testicular cancer. Estrogen signalling is critical for proper descent of the testicles, and hormonal imbalances play a role in cryptorchidism. CYP19, also known as aromatase, encodes an enzyme that converts testosterone, a male sex hormone, into estradiol, the main form of estrogen.