A study on the patterns of expression of the DAZ and HSP genes in the testicular tissue of men with azoospermia

Spermatogenesis is known to be regulated by a number of genes and several factors such as hormones, growth factors, cytokines and others. This study was done to evaluate the relationship between HSPs and DAZ genes in human spermatogenesis; we observed the expression pattern of HSP gene in azoospermia men with DAZ gene that regulated the gene expression related with human spermatogenesis. RT-PCR method was used to detect DAZ, HSP70A, and HSP70B transcripts in all RNA samples. Total RNA was extracted from 21 testis tissues using TRIZOL reagent. cDNAs were synthesized with reverse transcriptase, AMV. All PCR reaction were performed on a PCR themocycler with DAZ, HSP70A, and HSP70B-specific primers. Semen analysis, karyotyping and testis histology were performed. DAZ gene, known as a candidate gene of azoospermia factor(AZF), was deleted in 2 of 21 patients. To evaluate the only effects of HSPs in this patients, 2 DAZ deleted cases were removed. We observed the mRNA of HSP70B in 5 whereas none could be seen with regard to HSP70A. Furthermore, the sperm of these 5 men were discovered to be immature. In conclusion, HSP70B as well ad DAZ gene seem to be involved causing spermatogenic failure. We suggest that HSP70B plays an important role in spermatogenesis and it is one of factors induced sperm maturation in human.