spermaSORT, relief in the offing for ‘AS’ couples?

Olumide Adenmosun is an Adjunct Instructor for General Microbiology and Microbiology for Health Services at Florida Atlantic University, USA. His ongoing research on Assisted Reproductive Technology (ART) is towards producing a Condom for “AS” Couples called spermaSORT “Hb-A”. He speaks with VERA ONANA on the research which may help AS couples birth children without sickle cell disease.

What exactly is “spermaSORT Hb-A Condom”? Will it be the Holy Grail for carriers of the sickle cell gene?

SpermaSORT is a concept idea which I developed after working as an Embryologist Trainee and IVF-PR-consultant for a few IVF clinics in Nigeria. It is a device or bio-material which we hope to better develop for couples who might be at risk of birthing babies with the actual sickle cell disease(SCD). Usually those common risk groups are couples with the AS/AS; AC/AS; AS/SS or AC/SC as the husband and wife’s blood genotype respectively.

What spurred your research?

The major reason why I started working on this project was because I belong to the AS/AC genotype risk group. While I worked as an Embryologist Trainee, I remember we had some clients in similar risk groups wanting to consider assisted reproductive options to prevent the recurrence of a sickle cell birth – in situations where not knowing their individual genotypes, they might have already given birth to a child with SCD; or for those who knew their genotypes, but seeking to minimise their risks of an SCD conception. The only available assisted conception procedure for couples in such categories is called IVF/PGD – which is Preimplantation Genetic Diagnosis following In vitro Fertilisation.

Using that procedure, eggs fertilised by the husband’s sperm outside the womb in Petri dishes or via Intra-Cytoplasmic Sperm Injection (ICSI) can be genetically tested at about day three to five of embryonic development. Embryos’ genotypes can be determined by PGD and healthy embryos without the sickle cell genes (or at least not in the homozygous state) will only be transferred back to the womb to give them a shot at establishing pregnancy.

So what happens to those embryos that carry the sickle cell genes?

Well, they could be cryopreserved perpetually, donated ethically for stem cell research or out-rightly discarded. And there’s the dilemma right there. So I thought, rather than tamper with those embryos, some of which may be eventually discarded; why not create a methodology that enables one to ensure that the sperm cells that harbour the sickle cell genes are sorted out from the mix and fertilisation can only be completed with those sperms bearing the “Hb-A” gene; then all embryos will be viable for transfer except for those that don’t make it naturally. Hence the name spermaSORT “Hb-A” condom. The idea was to create a voided condom (one with an opening) that is capable of filtering sperm cells with the “Hb-A” gene only.

How far into this research have you gone?

Though the idea seems like a holy grail, it does not certainly seem very practicable scientifically because the hemoglobin gene is not expressed in sperm cells and being able to characterise a sickle cell sperm may become a life-time scientific inquiry on its own. However, it is being hypothesised that there might be biomarkers present on the sperm membrane that may be able to give us that distinguishing information to help select for sickle cell sperms. So our research team started with a blind characterisation attempt with sickle cell monoclonal antibodies which we got from some scientists from another university – despite knowing that we should not find hemoglobin proteins on a sperm cell. Our preliminary results were inconclusive, but we observed some selective tagging of sperm cells with sickle cell monoclonal antibodies under a fluorescent microscope – a study we decided not to publish yet until we had perfected the methodology and repeated the study.

What makes SpermaSORT different from regular condoms?

We are still very far away from perfecting spermaSORT as it is still in its early stages of research; but the conceptual design has it as a kind of a condom with a filterable opening and a conjugation chamber with monoclonal antibodies that can trap and immobilise sickle cell sperms while the non-sickle cell sperms can freely swim through the opening to fertilise the egg waiting. The conceptual design can be found on our biotech startup’s website.

Don’t you think that sorting and killing certain ‘babies’ is a bit unorthodox?

I am pro-life and do not subscribe to abortion or anything that seems like it. I believe that life also starts from conception which is why I hope this study becomes successful and avails us a more ethically acceptable method of selecting embryos without the sickle cell genes. While we hope spermaSORT can become the DIY (Do-It-Yourself) version of the methodology, for those with excellent sperm parameters; we are also working on an in vitro laboratory guided method that can be utilised in a novel “IGSI” technique (Intracytoplasmic Genotypically-selected Sperm Injection) which we also hope to introduce someday.

How well do you think Nigerians will receive this innovation?

Well, maybe time will tell. We hope we can establish that it even works first.

IVF/PGD is almost always very expensive, are your condoms going to be cheaper?

The last time I checked, IVF/PGD costs about N3.6 million for one cycle at a top IVF clinic in Abuja. It might be too early to prospect for spermaSORT, but I hope it may be quite accessible and affordable for the at risk groups that need it when it becomes available and approved as being safe to use.

I understand that normal condoms are not 100 per cent effective in preventing pregnancies, is your Hb-A above missing the target?

I was asked a similar question when I went to give a presentation on spermaSORT at a teaching hospital in Miami, Florida with my Professor working with us on the project. The condom will only reduce the chances of having an SCD conception. Without any other control measure in place, an AS/AS couple for example has a 25 per cent chance of giving birth to a sickle cell baby. We are not certain that spermaSORT can efficiently screen through an ejaculate with an average of 20million spermatozoa from a heterozygous subject (AS genotype) and filter out all the sickle cell sperms. But we surmised that any control measure that further drops the chances below 25 per cent  is worth working on.