DNA integrity is a critical molecular indicator for the assessment of male infertility

Traditional semen analysis is routinely used for the assessment of male infertility. The present study aimed to evaluate the application of molecular techniques in determining the DNA integrity of the spermatozoa of infertile men in comparison to conventional analysis. Semen samples from 52 infertile patients were analyzed by conventional assays, flow cytometry (FCM) analysis for sperm DNA integrity and colorimetric assays for total antioxidant capacity (TAC). The traditional semen analyses showed that 48.1% of the patients had normospermic samples. The figure decreased to only 25% following the application of molecular tests. DNA FCM revealed that 67.3% of the patients had an abnormal chromatin status (n=36), while at the same time, 36% showed aneuploidy features (n=19), and 59.6% had an abnormal TAC level (n=31). The normozoospermic samples had less DNA fragmentation and a higher mean seminal plasma TAC level (1,500.92±280.29 µM) than the abnormal samples (899.59±375.67 µM). Significant correlations were noted between chromatin condensation and the sperm count (r=587, P<0.001), motility (r=0.625, P<0.001), normal morphology (r=0.658, P<0.001) and white blood cell (WBC) count (r=‑0.299, P<0.005). In addition, the infertile subjects with abnormal chromatin condensation had significantly lower TAC levels than the other subjects and the level was markedly decreased in the samples with severe abnormalities (class 7 and 8). The presence of the aneuploidy cells was negatively correlated with the sperm concentration (r=‑0.339, P<0.005). In conclusion, traditional semen analysis has limited value in the prediction of male fertility and should be combined with other molecular tests to increase its sensitivity.