q regarding antiquated sperm sorting technology

[atomic sagebrush]

Sorry to bother you again, but I was wondering about the various methods of sperm sorting techniques that I've read about in various places, particularly FISH vs. quinacrine staining (and any other antiquated methods that you are aware of.) My understanding is that quinacrine has been dropped as unreliable and so when I am presented a study that uses quinacrine staining (or dates back more than 15 years or so) I should not give it much merit, but I am not sure on the particulars of how and why and I would like to be able to explain it to people.

Huge thank you!!!

[Carole]

Hi Atomic sagebrush,

Here's a link to a review of sex selection laboratory methods including sperm selection methods which may be useful http://www.hfea.gov.uk/docs/Appendix_C_-_Scientific_and_Technical_Literature_Review.pdf

Here's a link to reference and short abstract Determination of sex ratio of spermatozoa with... [Fertil Steril. 1992] - PubMed - NCBI (http://www.ncbi.nlm.nih.gov/pubmed/1378794?dopt=Abstract)
that discredits Percoll gradient separations for gender selection. It seems the main criticism was that they used quinacrine stain to identify the success of their separation and the staining method was unreliable.

In sperm labs, we separate sperm on Percoll or Percoll-like gradients every day but we are selecting for motile normal sperm which pass through the gradient. non-motile sperm, ill formed sperm and debris in the ejaculate gets hung up in the thickish percoll layer. It is not useful for separating x and y bearing sperm.

Microsort is a method developed for use in domestic animals first but then adapted for human sperm. Unlike most other methods, microsort does work to enrich a sample for either x or y bearing sperm (X enrichment may work a little better). Possible downsides to microsort is that it is not 100% enrichment (the opposite gender sperm are there but in reduced amount) and the technique uses a laser to sort and fluorescent dyes which bind to the sperm DNA -either of which could theoretically damage the DNA in the sperm. Kids that are apparently healthy are born using this technique but we don't have decades of outcome data either so we can't declare it 100% safe forever for everyone.
Hope this helps,
Carole

[ashkash]

Very interesting! I can't wait to read it all more thoroughly when I can find a few minutes of quiet.

[atomic sagebrush]

Thank you so much Carole, those are GOLD!!! So very helpful. I really appreciate it!!