Frequency of AZF microdeletions in azoospermic men candidate for micro TESE

Background: The Y chromosome accumulates male-related genes including sex-determining region of Y-chromosome (SRY) and several spermatogenesis-related genes. The long arm contains azoospermia factor (AZF) region (including sub-regions AZFa, AZFb and AZFc).Objective: Microdeletions in this region are responsible for azoospermia and oligospermia and results in the male infertility. The aim of this study was to analyze incidence of microdeletions in the AZF region of Y chromosome in patients with azoospermia from Iran.Materials and Methods: Over the period from 2016 to 2018 a total of 358 men were analyzed. The diagnosis of azoospermia was established on the basis of semen analysis. All patient samples were analyzed cytogenetically. Chromosomal analysis was performed on all patients on cultured lymphocytes from peripheral blood. For exact diagnosis of microdeletions in AZF region we used a PCR-method using a set of sequence-tagged sites from all AZF sub-regions (according to the recommendation by the European Academy of Andrology (EAA) and the European Molecular Genetics Quality Network (EMQN).Results: Among of all patients with azoospermia and normal karyotype, 11% of patients had microdeletions in the AZF region of the Y chromosome. Among of all patients with microdeletions were 3.9% microdeletions in the AZFc region, 2.5% microdeletions in the AZFb region and 1.2% microdeletions in the AZFa region. Men with isolated AZFc deletion, sperm were found in 50% by mTESE, although in some cases they did not have a good morphology.Conclusion: The study confirmed that percentage of microdeletions in the AZF region in Iranian azoospermic patients is similar to the global rate and Microdeletion of the entire AZFa or AZFb regions of the Y chromosome portends an exceptionally poor prognosis for sperm retrieval, whereas the majority of men with AZFc deletion have sperm within the semen or testes available for use in IVF/ICSI.

Keywords:

AZF , mTESE