Flow sorting of X and Y chromosome-bearing spermatozoa into two populations

Gamete Res. 1987 Jan;16(1):1-9. doi: 10.1002/mrd.1120160102.


The only established difference on which to base the separation of X and Y chromosome-bearing spermatozoa is chromosomal constitution. This difference is quantifiable both from chromosome morphology (karyotype) and from DNA content. Flow cytometric techniques were used to measure relative DNA content of the X and Y populations and to flow-sort spermatozoa from Chinchilla laniger. Epididymal spermatozoa were recovered in PBS, fixed in 80% ethanol, treated with papain and dithioerythritol, and stained for DNA with Hoechst 33342. Sperm nuclei were analyzed and sorted on an EPICS V flow cytometer/cell sorter, modified specifically for spermatozoa. Two clearly resolved peaks (coefficient of variation less than 1.5%) with approximately 7.5% difference in DNA content between X and Y chromosome-bearing spermatozoa were evident. Sperm nuclei were sorted from a portion of the X and Y peaks at a rate of 55 nuclei/sec for each population. Purities of individual X and Y populations averaged 95% as determined by reanalysis of the sorted populations. Successful sorting of Chinchilla X and Y chromosome-bearing spermatozoa into separate populations may aid in the identification of a biochemical marker that could be used to discriminate between the two sperm populations and lead to a practical procedure for sexing spermatozoa.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cell Separation
  • Chinchilla
  • DNA
  • Flow Cytometry / methods*
  • Male
  • Spermatozoa / cytology*
  • X Chromosome
  • Y Chromosome


  • DNA