Tuesday, 3 February 2015

Three Person IVF

Channel 4 News did a piece on this last night, ahead of today's vote in the House of Commons on the issue. They had two spokeswomen for the new procedure and one against. The one against came over badly, although I think the edge to her voice was mostly down to nerves - the other two seemed much more practised speakers.

The issue is about preventing some very nasty diseases caused by faulty mitochondria - tiny organelles in the cell which are mostly responsible for generating the cell's energy. They are not a part of the cell nucleus, so they are not affected by the normal mixing of genes in sexual reproduction, although each does have its own small parcel of DNA. Instead they are passed directly from a mother to all her children. When mitochondria go wrong this can lead to whole families having some horrible diseases.

One thing that I don't like about media presentations of the issue is that they are less than clear about the procedures involved. The proposed amendments basically allow two different sorts of intervention in the IVF process: 'egg repair' (shown above) and 'embryo repair'. The former takes a donor egg, removes the nucleus and replaces it with the nucleus from the mother's egg. The resulting egg is then fertilised with the father's sperm.

'Embryo repair' is superficially very similar: essentially you do the same thing but with two embryos rather than two eggs. Media presentations, including Channel 4's last night, show 'egg repair' and don't mention the embryo option. The BBC - to its credit - did show both options, near the bottom of its online piece. Other reports I have seen get it completely wrong and talk about moving the healthy mitochondria into the mother's egg to replace the damaged ones; this is not what is proposed.

So what's the problem? Surely preventing horrible diseases is good. Isn't this really just another step on from standard IVF?

The issue with 'embryo repair' is straightforward, I think. It is not really repairing an embryo, so much as creating one embryo solely to be used as a carrier for another embryo's genetic material. Essentially creating embryos for use as spare parts. That is a big ethical jump, one that I find both obnoxious in itself, and scary in the options it opens up: why not remove an embryo's brain and grow it to full term as a source of replacement liver and kidneys for a rich old man, for instance? Also there are major safety concerns with what is essentially cloning technology.

'Egg repair' - again you're not actually repairing anything, more transferring a nucleus into a fresh egg - is trickier. One big objection being made is that it may not be safe. IVF itself turns out to have odd side effects which are only recently being successfully addressed, and that is a far less drastic operation.

The weakness in that argument is that having a child the 'natural' way is pretty much guaranteed to be unsafe, to pass on the mitochondrial disease. Although it is very likely that there would be unexpected side effects in the early years of such a procedure, the probability of them being worse than the original disease is low, I suspect.

The main British church groupings have spoken out against the procedure: Roman Catholics here; the Church of England official statement is here. There was recently a warning about interactions between mitochondrial and nucrlear DNA in New Scientist here; although in general British scientists seem decidedly gung-ho about leading the world in this area.

An issue briefly raised in Channel 4's piece is that this would, at best, only prevent mitochondrial disease in children conceived in this way, it is not a cure for existing sufferers. You could get the same effect if those who know they have faulty mitochondria simply did not have children. The response highlighted that this really is the old issue around IVF of 'a woman's right to have children' if she wishes.

Personally, I hope that MPs reject the 'embryo repair' option today. But on the general principle of 'three-parent' babies, I think we live in a complex time for families, and it would be better for individual Christians and local churches to focus on the point that people matter to God. All sorts of people: people with families and people without; people with genetic impairments and those without; people conceived with and without scientific help. Each and every individual person matters deeply to God; hopefully they also matter to us.

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