What Is the TUNEL Technique?
The TUNEL technique (Terminal Transferase dUTP Nick End Labeling) is a method used to evaluate sperm DNA quality, as it assesses DNA integrity and detects genetic damage.
The TUNEL test is recommended when:
- There is unexplained male infertility.
- There have been recurrent fertilization failures or suboptimal embryo development during IVF/ICSI procedures.
- There have been recurrent miscarriages with no apparent cause.
- The male partner is of advanced age.
The presence of sperm DNA damage impairs the sperm’s ability to fertilize the egg and affects the proper development of the embryo.
Performing the TUNEL technique does not require any action from the patient beyond providing a semen sample.
Once the sample reaches the lab, it is processed in a way that marks the broken DNA strands, allowing them to be detected by flow cytometry or fluorescence microscopy.
A fragmentation value exceeding 15-30>#/b### is considered high and can significantly impair semen quality.
Knowing the degree of sperm DNA fragmentation is very useful when planning the best strategy for a fertility treatment and preventing associated complications.
The main alternatives to the TUNEL technique for measuring sperm DNA fragmentation include: SCSA test (Sperm Chromatin Structure Assay), COMET technique (Single Cell Gel Electrophoresis), Sperm chromatin dispersion assay or sperm selection techniques such as MACS and PICSI.