SERPINE1 and Infertility: In addition, total t-PA concentration, plasminogen activator inhibitor-1 /t-PA complex concentration, and t-PA activity in seminal plasma were measured by enzyme-linked immunosorbent assay.<h4>Results</h4>The results indicate that the percentage of infertile participants (n = 50) who were homozygous for <i>t-PA</i> <i>Alu</i> insertion (<i>Alu</i>  + / +   ), heterozygous <i>Alu</i>  + / -   or homozygous for <i>t-PA</i> <i>Alu</i> deletion (<i>Alu</i>  - / -   ) did not change significantly (p = 0.43, 0.81, and 0.85, respectively) when compared with the control participants (n = 29).