A comparison of three different techniques to assess sperm DNA fragmentation

Abstract

OBJECTIVE: To Compare the Sperm Chromatin Dispersion Test (SCD), and the Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay (TUNEL) to the Sperm Chromatin Structure Assay (SCSA), considered the gold standard for the analysis of sperm DNA fragmentation.DESIGN: Prospective study. Semen samples of infertile men were analyzed to assess DNA fragmentation by three different techniques.MATERIALS AND METHODS: Each of 17 semen samples was divided into four aliquots: one to analyze sperm motility, morphology and concentration, and each of the other three to assess DNA fragmentation by SCD, TUNEL and SCSA. We performed Spearman correlation and linear regressions between percent of sperm with fragmented DNA determined by each of the techniques. P < 0.05 was considered statistically significant.RESULTS: A significant correlation (P<0.001) was found between the percents of DNA fragmentation as measured by SCD, TUNEL and SCSA. Both SCD and TUNEL showed a strong relationship with the SCSA (r >0.8, P<0.0001). Additionally, there was a negative correlation between sperm motility, morphology and concentration and the percentages of sperm DNA fragmentation.CONCLUSIONS: DNA fragmentation of human spermatozoa can be efficiently evaluated by SCD or TUNEL, as both showed a significant correlation to SCSA. We consider that DNA fragmentation evaluation should be included in the clinical semen analysis and its assessment could be performed by either SCD or TUNEL, in those Laboratories lacking the specialized equipment and technicians that SCSA requires. OBJECTIVE: To Compare the Sperm Chromatin Dispersion Test (SCD), and the Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay (TUNEL) to the Sperm Chromatin Structure Assay (SCSA), considered the gold standard for the analysis of sperm DNA fragmentation. DESIGN: Prospective study. Semen samples of infertile men were analyzed to assess DNA fragmentation by three different techniques. MATERIALS AND METHODS: Each of 17 semen samples was divided into four aliquots: one to analyze sperm motility, morphology and concentration, and each of the other three to assess DNA fragmentation by SCD, TUNEL and SCSA. We performed Spearman correlation and linear regressions between percent of sperm with fragmented DNA determined by each of the techniques. P < 0.05 was considered statistically significant. RESULTS: A significant correlation (P<0.001) was found between the percents of DNA fragmentation as measured by SCD, TUNEL and SCSA. Both SCD and TUNEL showed a strong relationship with the SCSA (r >0.8, P<0.0001). Additionally, there was a negative correlation between sperm motility, morphology and concentration and the percentages of sperm DNA fragmentation. CONCLUSIONS: DNA fragmentation of human spermatozoa can be efficiently evaluated by SCD or TUNEL, as both showed a significant correlation to SCSA. We consider that DNA fragmentation evaluation should be included in the clinical semen analysis and its assessment could be performed by either SCD or TUNEL, in those Laboratories lacking the specialized equipment and technicians that SCSA requires.