title: [AZF microdeletions on the Y chromosome in infertile Chinese men: a five-year retrospective analysis].
abstract: OBJECTIVE
  The past few years have seen great progress in the studies of the relationship between AZF microdeletions and male infertility. However, some molecular and clinical concerns are not supported by definitive data. The aim of this study was to investigate the prevalence and types of AZF microdeletions in infertile Chinese men, and the indications for genotype-phenotype correlation.
  
  
  METHODS
  We retrospectively analyzed Y chromosome AZF microdeletions among 502 patients with nonobstructive azoospermia and 306 with severe oligozoospermia received in our hospital during the past five years.
  
  
  RESULTS
  Microdeletions were detected in 7.80% of the patients (63/808), 9.16% in the men with nonobstructive azoospermia (46/502) and 5.56% in those with severe oligozoospermia (17/306). Complete AZFa and AZFb (P5/Proximal P1) deletions were associated with azoospermia, whereas AZFc deletion with variable spermatogenic phenotypes. A mild decline in sperm concentration was found in one male with partial AZFb deletion. The most frequent deletion was the AZFc b2/b4 subtype (60.32%, 38/63), and 39.47% of the cases (15/38) had sperm in the ejaculate. Of the 63 deletions, only one case of the AZFc b2/b4 type had a sperm concentration of over 2 million sperm/ml.
  
  
  CONCLUSIONS
  AZF microdeletions play a significant role in the diagnosis and evaluation of spermatogenic defects. Larger-scale clinical researches on Y chromosome microdeletions may give us a deeper insight into their mechanism and the genotype-phenotype relationship.
authors.affiliation: Center for Reproduction and Genetics, Research Institute of Clinical Laboratory Medicine, Nanjing University School of Medicine/Nanjing General Hospital of Nanjing Military Region, Nanjing, Jiangsu 210002, China.
authors.forename: Yi-Chao
authors.initials: YC
authors.lastname: Shi
authors.forename: Yi-Xia
authors.initials: YX
authors.lastname: Cui
authors.forename: Li
authors.initials: L
authors.lastname: Wei
authors.forename: Yu-Chun
authors.initials: YC
authors.lastname: Zhou
authors.forename: Yong
authors.initials: Y
authors.lastname: Shao
authors.forename: Xin-Yi
authors.initials: XY
authors.lastname: Xia
authors.forename: Xue-Jun
authors.initials: XJ
authors.lastname: Shang
authors.forename: Wei-Ming
authors.initials: WM
authors.lastname: Zhu
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Huang
mesh_terms: D000328:Adult; D044466:Asian People / Q000235:genetics; D053713:Azoospermia / Q000235:genetics; D002872:Chromosome Deletion; D041322:Chromosomes, Human, Y; D056426:Genetic Loci; D006801:Humans; D008297:Male; D008875:Middle Aged; D009845:Oligospermia / Q000235:genetics*; D012189:Retrospective Studies; D029589:Seminal Plasma Proteins / Q000235:genetics*; D017384:Sequence Deletion; D055815:Young Adult
chemical_list: D029589:Seminal Plasma Proteins