Efficient combined FISH and PRINS technique for detection of DAZ microdeletion in human sperm

Intracytoplasmic sperm injection (ICSI) now offers an effective therapeutic option for men with male infertility and is believed to allow transmission of genetically determined infertility to the male offspring. Transmission of DAZ (Deleted in Azoospermia) microdeletion is one of the major concerns for oligo and severe oligozoospermia patients. Screening of the Y chromosome microdeletion in the diagnostic work-up of infertile men is mainly done using polymerase chain reaction (PCR) on blood leukocytes. However, there are evidences showing that presence of DAZ in somatic cells might not be indicative of its presence in germ cell lineage. In this report we are going to describe a combined Primed in situ labeling (PRINS) and fluorescence in situ hybridization (FISH) technique to show the localization of DAZ gene as well as Y chromosome centromere on sperm nuclei. PRINS is a combination of FISH and in situ polymerization provides another approach for in situ chromosomal detection. In the present study the PRINS primers specific for DAZ genes and traditional direct labeled centromere FISH probes for Y and X chromosomes were used in order to simultaneously detect DAZ genes and sex chromosome aneuploidy in sperm samples.