Male factor infertility is -increasingly- being addressed in important studies and scientific publications. And although the most basic test in the study of infertility is the semen analysis, when additional information is needed we can turn to more specific tests such as the sperm DNA Fragmentation analysis, sperm FISH analysis, karyotyping and cystic fibrosis studies.
As regards sperm DNA Fragmentation, up until now this analysis examined the fragmentation of single-stranded DNA in spermatozoids.
What does this mean?
DNA is located in the nucleus of the sperm cell and contains the chromosomes and all genetic information which the male will pass on to his offspring. This genetic information is stored in a compact form in the nucleus, but if it were ‘decompacted’ it would consist of two parallel strands that can connect together. These strands are the instructions for the identity of offspring.
As we mentioned before, up until now single-stranded fragmentation studies were performed and techniques were used to process the samples and eliminate this fragmentation. At present, however, studies are being carried out not only on single-stranded fragmentation, but also on double-stranded fragmentation. It appears as though repairing this fragmentation is not so simple when both strands of DNA are damaged, thus affecting the rate of development of both the embryo and the pregnancy.
Therefore, advances are being made in techniques for the elimination of sperm with double-stranded fragmentation in samples to be used for ICSI.
Dr. Dermirci of Stanford University has now developed a microfluidic technique known as Fertile Chip. It is a sperm-sorting mechanism based on motility, as the motility of spermatozoids with double-stranded fragmentation is unique. By using microfluidics, this mechanism is able to select those spermatozoids that are positive for fragmentation without altering their DNA.
This technique is currently used at Ginemed and some 10,000 births recorded in the United States, Europe and Turkey have already used this technology.
Head Embryologist at Ginemed Murcia Assisted Reproduction Laboratory