Micro-deletions in the three non overlapping regions of the Y chromosome (AZFa, AZFb and AZFc) are associ­ated with male infertility. The vast majority of Y micro-deletions have been found in patients with azoospermia and severe oligozoospermia. Deletions of the azoospermia factor (AZF) regions have been associated with a spectrum of spermatogenesis defects, and there is still no clear geno­type/phenotype relationship. The knowledge about the presence of a Y micro-deletion in an infertile male has an important role for genetic counseling of the infertile cou­ple and for their decision concerning their therapeutic options.

The aim of this study was to evaluate the frequency of Y micro-deletions among an infertile male population from the Republic of Macedonia. A total of 109 infertile men and a control group of 50 proven fathers were stud­ied. The screening for Y micro-deletions was performed on genomic DNA by two multiplex polymerase chain reaction (PCR) analyses. A total of six sequence tagged sites (STSs), two in each AZF region,were analyzed.

A total of seven Y micro deletions were detected; six AZFc deletions and one AZFb+c deletion. No deletion was detected in the AZFa region. The Y micro-deletions were detected in six patients with azoospermia and one with severe oligozoospermia. No deletion was found among the fertile males, patients with normozoospermia and mild oligozoospermia (>5 x 10⁶/mL).

The prevalence of Y micro-deletions among the infer­tile males from the Republic of Macedonia is 6.4%, among patients with azoospermia 16.7%, and among those with severe oligozoospermia 2.8%. Different testicular defects were found among the patients with AZFc dele­tions [Sertoly-cell-only syndrome (SCOS) and hyposper­matogenesis]. The deletion was detected in six patients with idiopathic infertility and in one patient with vari­cocele. Family studies in one patient with an AZFc dele­tion have shown that the deletion has arisen as a de novo event.

Key words: Y micro-deletions; azoospermia factor (AZF); Sertoly-cell-only syndrome (SCOS); Infertility.