title: Measurement of sperm DNA fragmentation using bright-field microscopy: comparison between sperm chromatin dispersion test and terminal uridine nick-end labeling assay.
abstract: OBJECTIVE
  To compare sperm chromatin dispersion (SCD) test with terminal deoxynucleotidyle transferase-mediated terminal uridine nick-end labeling (TUNEL) assay in assessing DNA fragmentation in human sperm through bright-field microscopy.
  
  
  METHODS
  Prospectively designed, side-by-side comparative study.
  
  
  METHODS
  Medical genetics laboratory in a provincial research institution.
  
  
  METHODS
  Sixty male patients presented for infertility evaluation and 30 fertile, volunteer sperm donors.
  
  
  METHODS
  Semen analysis, SCD test, and TUNEL assay on the same semen sample and on the same spermatozoa.
  
  
  METHODS
  Sperm DNA fragmentation, determined by SCD test score or TUNEL assay score.
  
  
  RESULTS
  Sperm chromatin dispersion test and TUNEL assay identified similar proportions of sperm cells with DNA fragmentation in the same semen samples. When the SCD test and TUNEL assay were performed simultaneously on the same spermatozoa, TUNEL-negative sperm showed a large halo, whereas TUNEL-positive sperm showed no halo after Diff-Quik staining. However, in some sperm cells, DNA damage was detected by the SCD test but not by the TUNEL assay.
  
  
  CONCLUSIONS
  Sperm chromatin dispersion test and TUNEL assay are both effective in detecting sperm DNA damage. Using bright-field microscopy, the SCD test appears to be more sensitive than the TUNEL assay.
authors.affiliation: Department of Reproductive Medicine, Shandong Research Institute for Family Planning, Jinan, China. lihong01118@126.com
authors.forename: Li-hong
authors.initials: LH
authors.lastname: Zhang
authors.forename: Yi
authors.initials: Y
authors.lastname: Qiu
authors.forename: Ke-hua
authors.initials: KH
authors.lastname: Wang
authors.forename: Qiuju
authors.initials: Q
authors.lastname: Wang
authors.forename: Guozhen
authors.initials: G
authors.lastname: Tao
authors.forename: Lei-guang
authors.initials: LG
authors.lastname: Wang
mesh_terms: D000328:Adult; D048430:Cell Shape; D042002:Chromatin Assembly and Disassembly / Q000502:physiology; D053938:DNA Fragmentation; D005298:Fertility / Q000235:genetics / Q000502:physiology; D006801:Humans; D020287:In Situ Nick-End Labeling / Q000379:methods*; D007248:Infertility, Male / Q000235:genetics / Q000378:metabolism; D008297:Male; D008853:Microscopy / Q000379:methods*; D055101:Semen Analysis / Q000379:methods; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure*