title: Susceptibility to idiopathic azoospermia in Japanese men is linked to HLA class I antigen.
abstract: OBJECTIVE
  Approximately 15 to 20% of infertile men have azoospermia. In the Y chromosome a deletion, termed the azoospermic factor, has been found in some cases of idiopathic azoospermia. We investigate the relationship of factors in autosomal chromosomes (HLA class I antigens) to spermatogenesis failure in idiopathic azoospermia.
  
  
  METHODS
  We evaluated 65 infertile Japanese men with idiopathic azoospermia. The frequency of the HLA allele reported in 1,216 healthy Japanese men was used as a control. HLA class I typing was performed by the National Institutes of Health standard serological method or polymerase chain reaction-sequence specific primer analysis. Allele frequencies were calculated. We determined statistical significance in the frequency of each allele in patients and controls using the chi-square test. The relationship of HLA antigens to idiopathic azoospermia was expressed as relative risk.
  
  
  RESULTS
  In Japanese men with idiopathic azoospermia the frequency of HLA-A33, B13 and B44 was significantly increased compared with controls. The relative risk of HLA-B44 was 8.4, an extremely high value compared with that of other diseases and HLA antigens.
  
  
  CONCLUSIONS
  We suggest that HLA class I antigens are important genetic markers that represent a risk factor for idiopathic azoospermia.
authors.affiliation: Department of Urology, Osaka Police Hospital, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Miura
authors.forename: A
authors.initials: A
authors.lastname: Tsujimura
authors.forename: K
authors.initials: K
authors.lastname: Nishimura
authors.forename: M
authors.initials: M
authors.lastname: Kitamura
authors.forename: N
authors.initials: N
authors.lastname: Kondoh
authors.forename: M
authors.initials: M
authors.lastname: Takeyama
authors.forename: H
authors.initials: H
authors.lastname: Fujioka
authors.forename: M
authors.initials: M
authors.lastname: Sada
authors.forename: T
authors.initials: T
authors.lastname: Tsuji
authors.forename: K
authors.initials: K
authors.lastname: Matsumiya
authors.forename: S
authors.initials: S
authors.lastname: Takahara
authors.forename: A
authors.initials: A
authors.lastname: Okuyama
mesh_terms: D000483:Alleles; D004198:Disease Susceptibility; D015234:HLA-A Antigens; D015235:HLA-B Antigens; D059948:HLA-B44 Antigen; D015395:Histocompatibility Antigens Class I / Q000235:genetics; D006801:Humans; D007564:Japan; D008297:Male; D009845:Oligospermia / Q000235:genetics / Q000276:immunology*; D016133:Polymerase Chain Reaction; D012307:Risk Factors; D013091:Spermatogenesis / Q000235:genetics / Q000276:immunology
chemical_list: D015234:HLA-A Antigens; C082945:HLA-A*33 antigen; D015235:HLA-B Antigens; D059948:HLA-B44 Antigen; D015395:Histocompatibility Antigens Class I