P–020 AZFc partial microdeletions of the Y chromosome is associated with severe oligozoospermia among Iranian men

Abstract

Abstract Study question Are AZFc partial deletions correlated with severe oligozoospermia in Iranian men? Can we consider them as risk factors for infertility? Summary answer The frequency of total partial AZFc microdeletions was significantly higher in the oligozoospermia group compared to control group (8% vs. 3%, P = 0.028). What is known already Among many factors affecting male infertility, the second most common genetic factor is Y chromosome microdeletion. Some studies on partial AZFc microdeletions (especially on three major types; gr/gr, b1/b3 and b2/b3) have associated them with impaired spermatogenesis (azoospermia and oligozoospermia) in infertile men from different ethnicities. This finding is attributed to differences in alterations in pattern of DAZ/CDY1 copy numbers as spermatogenesis related genes. Study design, size, duration 200 oligozoospermic (sperm count <5 mil./mL) and 200 fertile men were included as case and control groups, respectively. Individuals with karyotype abnormalities, complete microdeletions in AZF regions, infections, hypogonadism, history of chemotherapy and radiation, cryptorchidism or history of orchiopexy were not included. The study was approved by the Royan Institute Ethics Committee. Written informed consents were obtained from each participant. Participants/materials, setting, methods Total DNA from peripheral blood was used to amplify six sequence-tagged sites (STS) markers through multiplex PCR to detect AZFc partial deletions according to previous studies. Patterns of deletion in DAZ and CDY1 copies were determined through PCR- RFLP. Main results and the role of chance The frequency of AZFc partial microdeletions was 8% in oligozoospermic men (16/200) which was significantly higher compared to 3% in control group (6/200) (P = 0.028). Hence, partial deletions may be considered as a risk factor for the male infertility in Iranian population. Also, gr/gr showed a higher frequency in oligozoospermic group (4%) compared to controls (1.5%) (P = 0.126). The combination of DAZ1/2+CDY1b was the most observed deletion pattern in 8 oligozoospermic men with gr/gr deletion (75%), while among 3 controls with gr/gr, DAZ3/4+CDY1a (2 out of 3) and DAZ3/4+CDY1b (1 out of 3) were detected. Therefore, DAZ1/2+CDY1b can be correlated to oligozoospermia. Limitations, reasons for caution In order to achieve stronger statistical results, a larger sample size is of more help. Wider implications of the findings: Risk of vertical transmission to male offspring and expansion in the size of deletions should be considered when providing ART services to infertile men. Genetic counseling is suggested in oligozoospermic men. Trial registration number -