FISH is a cytogenetic analysis technique that allows the identification of sperm chromosomes in an ejaculate or testicular biopsy sample. It determines the chromosomal endowment, expressing the percentage of spermatozoa that present alterations.
Usually 5 chromosomes are analyzed, 13, 18, 21, X and Y, as they are the most frequently affected chromosomes that can give rise to viable gestations. However, this study can be extended to other chromosomes.
Suggested for you: Fluorescent in situ hybridization (FISH): Alterations in Sperm Cells.