title: Lack of association between DAZ gene methylation patterns and spermatogenic failure.
abstract: BACKGROUND
  Abnormal DNA methylation of the male germ line is proposed as a possible mechanism causing compromised spermatogenesis in some men diagnosed with idiopathic infertility. Previous studies suggested that aberrant DNA methylation of several genes is associated with disruptions in spermatogenesis. However, little information is available on DNA methylation patterns of testis-specific genes in idiopathic male infertility.
  
  
  METHODS
  To investigate the association between DAZ gene methylation patterns and spermatogenic failure, we performed an analysis of methylation patterns in 174 idiopathic infertile patients and 58 fertile controls using bisulfite-modified sequencing.
  
  
  RESULTS
  We found that the methylation patterns of CpG island (CGI) in the DAZ gene promoter region were different between somatic cells and spermatic cells in the control group. DAZ gene methylation patterns among groups with different spermatogenic status were the same in somatic cells, completely methylated, and in spermatic cells. The results were concordant, except for the group with azoospermia (AZ) which were completely unmethylated.
  
  
  CONCLUSIONS
  Our data indicate that the methylation patterns of the DAZ gene are not associated with spermatogenic failure. This suggests that epigenetic modification of DAZ is unlikely to be involved in the etiology of spermatogenic failure.
authors.affiliation: Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.forename: Chuncheng
authors.initials: C
authors.lastname: Lu
authors.forename: Yankai
authors.initials: Y
authors.lastname: Xia
authors.forename: Ouxi
authors.initials: O
authors.lastname: Shen
authors.forename: Guixiang
authors.initials: G
authors.lastname: Ji
authors.forename: Aihua
authors.initials: A
authors.lastname: Gu
authors.forename: Ling
authors.initials: L
authors.lastname: Song
authors.forename: Xinru
authors.initials: X
authors.lastname: Wang
mesh_terms: D000328:Adult; D018899:CpG Islands; D019175:DNA Methylation; D000075364:Deleted in Azoospermia 1 Protein; D044127:Epigenesis, Genetic; D006801:Humans; D007248:Infertility, Male / Q000235:genetics*; D008297:Male; D011401:Promoter Regions, Genetic; D016601:RNA-Binding Proteins / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013091:Spermatogenesis / Q000235:genetics*; D013447:Sulfites / Q000737:chemistry
chemical_list: C095668:DAZ1 protein, human; D000075364:Deleted in Azoospermia 1 Protein; D016601:RNA-Binding Proteins; D013447:Sulfites; C042345:hydrogen sulfite