Cross SectionalHuman2013
Comprehensive analysis of sperm DNA fragmentation by five different assays: TUNEL assay, SCSA, SCD test and alkaline and neutral Comet assay.
Plain-language summary
This study set out to work out which sperm DNA fragmentation test best predicts male infertility. Sperm DNA fragmentation means breaks in the genetic material inside sperm, where more breaks mean a lower chance of conception. The researchers ran five tests on the same men, fertile donors and infertile patients, using the TUNEL assay, SCSA, the SCD test, and the alkaline and neutral Comet assays, then compared how well each one separated the two groups. Every test except the neutral Comet assay told fertile men from infertile men, and the alkaline Comet assay did it best. The study also set a cut-off value for each test.
Key findings
- Four of the five tests separated fertile from infertile men. A relationship was found for the alkaline Comet assay, the TUNEL assay, the SCD test and SCSA, and the alkaline Comet assay separated them most sharply.
- For the neutral Comet assay, no relationship was found. It did not separate the two groups at all.
- A cut-off was set for each test: 20.05 percent for TUNEL, 18.90 percent for SCSA, 22.75 percent for SCD, 45.37 percent for alkaline Comet and 34.37 percent for neutral Comet.
How to analyze the study yourself
- Study type
- This measured five tests in the same men at one point in time, so it shows which test separates fertile from infertile men best, and not whether acting on a high result changes anyone's chance of conceiving.
- Population
- The study included both fertile donors and infertile patients, but the exact number of participants was not reported.
- Funding
- Not reported
- Takeaway
- This study found that four of the five common sperm DNA fragmentation tests separated fertile from infertile men, the alkaline Comet assay best of all, while the neutral Comet assay did not separate them at all. If you are being worked up for infertility, it may be worth asking your doctor which test the lab runs, because a neutral Comet result would tell you nothing either way.