title: A frequent Y chromosome b2/b3 subdeletion shows strong association with male infertility in Han-Chinese population.
abstract: BACKGROUND
  Azoospermia factor c (AZFc) subdeletions were reported to be significant risk factors for spermatogenesis. In this study, we assessed the occurrence of classical AZF deletions and AZFc subdeletions and their impact on male infertility in a Han-Chinese population.
  
  
  METHODS
  This study analysed a population of 699 subjects, including 451 idiopathic infertile patients with a range of fertility disorders and 248 fertile controls, using a retrospective design. Deletions were identified by multiplex PCR.
  
  
  RESULTS
  The prevalence and phenotypes of the classical AZF deletions were similar to previous studies. Subdeletions of the AZFc region in patients showed similar overall frequencies in all sperm concentration categories of gr/gr (7.0%) and b2/b3 (8.9%). For controls, these subdeletions were also found with a prevalence of gr/gr (7.7%) and b2/b3 (3.2%). b1/b3 deletions were not found either in the patients or in the controls.
  
  
  CONCLUSIONS
  Our data showed a higher frequency of deletion events in this Han-Chinese population than in populations elsewhere in the world. The classical AZF deletions were the primary genetic factors for spermatogenic failure, while no significant association was found for AZFc subdeletions with sperm concentration. However, the b2/b3 subdeletion was significantly associated with idiopathic male infertility (odds ratio, 2.93; 95% confidence interval 1.34-6.39) (P = 0.005), indicating a potential impairment of male fertility.
authors.affiliation: The Key Laboratory of Reproductive Medicine of Jiangsu Province, Institute of Toxicology, Nanjing Medical University School of Public Health, Nanjing, China.
authors.forename: B
authors.initials: B
authors.lastname: Wu
authors.forename: N X
authors.initials: NX
authors.lastname: Lu
authors.forename: Y K
authors.initials: YK
authors.lastname: Xia
authors.forename: A H
authors.initials: AH
authors.lastname: Gu
authors.forename: C C
authors.initials: CC
authors.lastname: Lu
authors.forename: W
authors.initials: W
authors.lastname: Wang
authors.forename: L
authors.initials: L
authors.lastname: Song
authors.forename: S L
authors.initials: SL
authors.lastname: Wang
authors.forename: H B
authors.initials: HB
authors.lastname: Shen
authors.forename: X R
authors.initials: XR
authors.lastname: Wang
mesh_terms: D000328:Adult; D053713:Azoospermia; D002681:China; D002872:Chromosome Deletion; D041322:Chromosomes, Human, Y; D005298:Fertility; D017353:Gene Deletion; D005819:Genetic Markers; D006239:Haplotypes; D006801:Humans; D007248:Infertility, Male / Q000208:ethnology* / Q000235:genetics*; D008297:Male; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies
chemical_list: D005819:Genetic Markers