Deficiencies in sperm function are usually the result of spermatogenic defects. Spermatogenesis is a biologically complex and essential process during which spermatogonia undergo meiotic recombination, reduction of the genome to a haploid state, and extensive cellular modifications that result in a motile cell capable of traversing the female reproductive tract, withstanding various potential assaults to viability, and finally successfully fertilizing a mature oocyte to give rise to an embryo. Defects in any step of spermatogenesis or spermatogenesis can lead to male infertility, a disease...