Y-chromosomal microdeletions among infertile Finnish men

Background. Microdeletions in the Y-chromosome are known to cause a signifi cant proportion of azoo- and oligozoospermia in men. The reported frequency of deletions varies greatly between the studies. Probable reasons for this variation are different selection criteria and number of patients included , and possibly also methodological aspects, whereas the contribution of env ironmental and genetic factors is not known. The aim of this study was to d etermine the incidence of Y-chromosome microdeletions among infertile Finni sh men. Methods. Two hundred and one men showing azoospermia (n=68) or severe oligo zoospermia (n=133) were included. Multiplex polymerase chain reaction metho d was used to amplify specific sequence tagged sites (STS) along the Y chro mosome. Results. Microdeletions were observed in 18 men (9%), of whom four were azo ospermic and 14 oligozoospermic. Conclusions. The incidence of Y-deletions in the study population of infert ile Finnish men falls within the range published in other countries.