Analysis of Y-Chromosomal Microdeletions in an Azoospermic Patient Candidate for an Assisted Reproductive Technique

Abstract

Y-chromosomal microdeletions are the second most frequent genetic cause of male infertility. As stated in the guidelines of the European Academy of Andrology (EAA) for molecular diagnosis of Y-chromosomal microdeletions, this kind of analysis should be performed in patients with azoospermia or severe oligospermia with sperm concentrations <2 x106/mL. In these patients, it is also convenient to analyze other clinical parameters such as hormone levels, testicular volume, varicocele, infections etc, although these parameters do not have any predictive value. Here we report a laboratory case of an azoospermic patient candidate to a testicular sperm extraction (TESE) for performing an assisted reproductive technology. According to EAA guidelines, we first performed the multiplex PCR amplification of genomic DNA with the Ampli-Y Chromosome and Ampli-Y Chromosome Extension kits (Diachem, Italy). As a confirmatory test we also utilized the Devyser AZF kit (Devyser Ab, Sweden). The execution of karyotype was performed in an external laboratory. The Y-chromosomal microdeletions analysis performed showed a lack of AZF b and c regions of Y-chromosome, confirmed by both kit utilized for Y microdeletions diagnosis. The patient had also high levels of FSH and LH, low level of inhibin b, and normal levels of prolactin and testosterone hormones. Moreover after the execution of karyotype test, the patient was found to be carrier of a severe form of chromosomal mosaicism (45X[99]; 46XY[1]) that confirmed Y microdeletion diagnosis. Overall these results suggested clinicians to do not perform TESE since, as reported in literature, the chance for testicular sperm retrieval in these cases is virtually zero. Our case confirmed the need of a good laboratory practice to support clinical decisions.