[Meiotic recombination in unexplained human male infertility: an updated review]

During the prophase of meiosis I, homologous recombination plays a crucial role in the proper segregation of homologous chromosomes. Altered recombination may be an important risk factor for non-disjunction, which in turn contributes to infertility. Infertility is a major health problem that affects 10%-20% of couples, and about a half is attributed to male factors. Despite the obvious clinical significance of human male infertility, the mechanisms of spermatogenic failure caused by meiotic recombination errors in humans are inadequately known at present. However, recently-developed immunofluorescence methods, which enable us to directly view meiotic recombination events during gametogenesis, have revolutionized our understanding of human spermatogenesis.