Y chromosome microdeletions in infertile men with cryptorchidism

Objective: To determine whether cryptorchidism, associated with azoospermia or oligozoospermia may be due to microdeletions of the Y chromosome. Design: Controlled clinical study. Setting: Division of Medical Genetics and the Andrology Centre, Department of Obstetrics and Gynecology, University Medical Center, Ljubljana. Patient(s): Ninety men from infertile couples (36 azoospermics, 35 oligozoospermics, and 19 normozoospermics) with a medical history of cryptorchidism. Nineteen excryptorchid patients with cryptorchidism and Y chromosome microdeletions among 3099 patients from 14 publications. Intervention(s): Collection of semen and blood samples. Main Outcome Measure(s): Medical history, testicular volume, sperm characteristics, serum FSH levels, testicular histology, presence or absence of Y chromosome microdeletions, including all known Y chromosome genes/gene families in the azoospermia factor (AZF) region. Result(s): Deletions of the Y chromosome were found in 2 out of 71 cryptorchid patients with azoospermia or oligozoospermia (2.8%). The literature review showed that the incidence of microdeletions in infertile patients with cryptorchidism is lower in comparison with the general population of infertile men (4.9% vs. 8.1%), and that the frequency of cryptorchidism in patients with Y chromosome deletions (6 out of 103, 5.8%) is significantly lower in comparison to infertile patients without deletions (178 out of 1141, 15.6%). Conclusion(s): No causal relation exists between Y chromosome microdeletions and cryptorchidism.