SpermComet® is our proprietary technology powering Examen’s range of sperm DNA fragmentation tests. Independent research has shown that SpermComet® technology is the best performing DNA fragmentation tool in terms of sensitivity, specificity and predictive power, and is the only DNA fragmentation assay capable of handling surgically retrieved testicular sperm samples.
All sperm DNA tests are not the same. Available tests measure different aspects of sperm chromatin damage and as a result have variable levels of diagnostic strength (Table 1)
SpermComet® technology is based on a technique known as single cell gel electrophoresis (SCGE). This technique is used extensively in drug toxicity research.
Independent research has shown that the SpermComet® technology is the most sensitive assay for detecting DNA fragmentation (Figure 1 and 2)
This is due to several unique features of the assay:
Detects Actual DNA Fragments: SpermComet® technology detects single-stranded and double-stranded DNA breaks present in individual sperm, making it a direct assay of damaged DNA.
In contrast, Sperm Chromatin Dispersion arrays such as the SCSA and Halo assays only detect faults in the nuclear proteins protecting the sperm DNA. Damage to these nuclear proteins can make the DNA more vulnerable to damage, but it is not a direct measure of the actual damage to the sperm DNA itself.
Detects Total DNA Damage: Sperm DNA is up to 6 times more tightly packed than somatic cell DNA. The SpermComet® assay includes a step to relaxes the sperm DNA, exposing the DNA strand breaks in the nuclear core. This step is necessary to detect total and not just peripheral DNA damage.
Quantifies Amount of DNA Fragmentation: Separation of the DNA fragments contained in individual sperm nuclei during electrophoresis allows the amount of DNA fragments to be quantified. In contrast, the other assays only measure either the presence or absence of chromatin or DNA damage.
Independent research has shown that tests using SpermComet® technology are the best for differentiating between fertile and infertile men (Table 2). SpermComet® has a very high sensitivity and specificity in predicting male infertility.
The high sensitivity of the technology means that it detects a high proportion of true positives i.e. samples likely to achieve a spontaneous pregnancy.
The high specificity of the SpermComet® technology means that it also detects a high proportion of true negatives i.e. samples unlikely to achieve a spontaneous pregnancy.
