FISH on sperm

What is FISH on sperm?

One of the most important techniques developed in recent years is “ FISH”, from the initials of the words Fluorescence In Situ Hybridization. This test uses detector molecules that “carry” a fluorescent substance. The detectors “stain” the chromosomes and thus we have the ability to identify the number of chromosomes with the use of the fluorescent microscope.

What do we detect with FISH on sperm?

FISH has applications in the diagnosis of chromosomal abnormalities, which play a key role in fertility. When we test a semen sample with FISH we can check the integrity of the number of chromosomes present in its nucleus. During cell division, if meiosis is not done properly, there are more chromosomes in the spermatozoon than necessary so we have polyploidy. Conversely, if there are fewer chromosomes, then the embryo will suffer from aneuploidy.

Which chromosomes do we detect with the use of FISH on sperm?

In cases where the karyotype of the man is normal, chromosomes 13, 18, 21, 22, X, Y are tested, which can give live embryos. However, if a karyotypic abnormality has been detected then more chromosomes can be included.