title: Male infertility and its genetic causes.
abstract: OBJECTIVE
  Infertility is a serious social problem in advanced nations, with male factor infertility accounting for approximately half of all cases of infertility. Here, we aim to discuss our laboratory results in the context of recent literature on critical genes residing on the Y chromosome or autosomes that play important roles in human spermatogenesis.
  
  
  METHODS
  The PubMed database was systematically searched using the following keywords: 'genetics of male factor infertility'; 'male infertility genes', 'genetics of spermatogenesis' to retrieve information for this review.
  
  
  RESULTS
  Striking progress has recently been made in the elucidation of mechanisms of spermatogenesis using knockout mouse models. This information has, in many cases, not been directly translatable to humans. Nevertheless, mutations in several critical genes have been shown to cause male infertility. We discuss here the contribution to male factor infertility of a number of genes identified in the azoospermia factor (AZF) region on the Y chromosome, as well as the autosomally located genes: SYKP3, KLHL10, AURKC and SPATA16.
  
  
  CONCLUSIONS
  Non-obstructive azoospermia is the most severe form of azoospermia. However, the presence of spermatozoa can only be confirmed through procedures, which may prove to be unnecessary. Elucidation of the genes underlying male factor infertility, and thereby a better understanding of the mechanisms that cause it, will result in more tailored, evidence-based decisions in treatment of patients.
authors.affiliation: Department of Obstetrics Gynecology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Toshinobu
authors.initials: T
authors.lastname: Miyamoto
authors.affiliation: Department of Obstetrics Gynecology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Gaku
authors.initials: G
authors.lastname: Minase
authors.affiliation: Department of Obstetrics Gynecology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Kimika
authors.initials: K
authors.lastname: Okabe
authors.affiliation: Department of Obstetrics Gynecology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Ueda
authors.affiliation: Department of Obstetrics Gynecology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Sengoku
mesh_terms: D000818:Animals; D053713:Azoospermia / Q000235:genetics*; D006801:Humans; D008297:Male; D014998:Y Chromosome
keywords: AURKC; KLHL10; SPATA16; SYCP3; azoospermia factor; male infertility