Chromosomal variations in infertile men diagnosed by cytogenetic analysis

Abstract

Introduction. Male infertility has a heterogeneous etiology, most commonly caused by disorders of spermatogenesis, clinically manifested as azoospermia or severe oligospermia. Genetic factors account for approximately 30% of male infertility cases associated with azoospermia. This high frequency is due to the involvement of numerous genes in the regulation of sexual development and reproduction. Among the various genetic causes of spermatogenic failure, chromosomal abnormalities are among the most clinically significant. The objective of the study was to evaluate the profile of chromosomal variations in infertile men with azoospermia, to optimize assisted reproductive strategies in infertile couples. Material and methods. A group of 96 azoospermic men underwent karyotype analysis. The diagnosis of azoospermia was established based on at least two consecutive semen analyses performed according to the guidelines of the World Health Organization (WHO). Cytogenetic analysis was carried out on peripheral blood lymphocytes, with results interpreted according to the 2016 International System for Human Cytogenetic Nomenclature (ISCN). Hormonal profiles (FSH, LH, prolactin, testosterone) were correlated with chromosomal findings. Statistical analysis was performed using SPSS (Statistical Package for the Social Sciences), version 22.0. Results. Cytogenetic investigations in azoospermic patients (n = 96) revealed karyotype variations in 25.0% of cases, including sex chromosome abnormalities in 16.7%: 47,XXY – Klinefelter syndrome (11.5%); microscopic structural variations of the Y chromosome (2.1%); and single cases of 47,XYY – Jacobs syndrome; 46,XX male – sex reversal; and 45,X/46,XY – mixed gonadal dysgenesis. Autosomal abnormalities were found in 8.3% of cases: translocations (3.1%), inversions (2.1%), chromosomal polymorphisms (2.1%), and one case with 46,XY,fra(17)(p12). Patients with sex chromosome abnormalities exhibited significantly higher FSH and LH levels compared to those with autosomal abnormalities (p < 0.05), whereas prolactin and testosterone levels did not differ significantly between the groups. Conclusions. The high prevalence of chromosomal abnormalities in azoospermic men supports the inclusion of cytogenetic testing in the routine evaluation of male infertility. Identifying the type of chromosomal defect allows for appropriate genetic counseling and aids in decision-making regarding assisted reproductive options.