Rapid pre-implantation screening for IVF


IVF (in vitro fertilization) originally allowed couples suffering fertility issues to have children and it has been gloriously successful albeit pretty expensive. Since the fertilization of the egg and the sperm takes place outside of the mother, this also raises the possibility to first screen the mother’s egg or resulting fertilized embryos for any ‘genetic defects’ that we know will cause severe genetic diseases. Many developed countries now offer this service as way to give couples, who may suffer with or have a known family history of disease, the peace of mind their children will be unaffected. Beyond this screening may also be used to select embryos with a much higher chance of producing a baby to full term.

However IVF is not cheap and many couples may require several rounds of this process to get pregnant. Further still, this screening can add cost and time, it can take weeks to get back information on the genetics of each embryo to be tested, during this time the eggs/embryos will be frozen until it is deemed safe to implant into the mother. Further still, while they are waiting for the answers of screening, the mother may pass through another cycle or several, missing an opportunity to use those eggs for IVF.

Both the cost of sequencing (reading the genetic information of the cell) of the eggs/embryos, and the time the mother has to wait  until now has been avoidable.

Nanopore sequencing is based on the DNA molecule (genetic information) passing through a nanometre-scale (1 millionth of a mm) hole, as it does, the electrical current can be measured in real-time and from this we can work out the order of the A, T, G, and Cs that make up our genetic code. The real power in this new technique is the real-time readout, so in effect we can run the experiment until we find the answer we are interested in.

This is immediately applicable to IVF and pre-implantation screening/diagnoses, nanopore sequencing can give us the answer in matter of minutes. There is however still quite a bit of computing that needs to be done but recent work from Oxford Nanopore Technologies has been able to streamline this so that now, as soon as the eggs are harvested or embryos are fertilized they can get give the go ahead rapidly and potentially implant the embryos on the same day.

Nanopore sequencers are considerably smaller than current state-of-art platforms ( think the comparison of a drone compared to the a Airbus A380). This means all of this can potentially be done within a small clinic with very little equipment other than a flash drive and a powerful laptop computer.  Obviously this greatly reduces the price for the procedure, meaning even if implantation is not successful (it is something we still understand badly), the couple may be able to afford a further round of IVF. Ultimately this also greatly reduces the anxiety and burden for the hopeful parents, something which you cannot put a price on.