And Baby Makes Three

The UK looks like it will be the first country to allow babies with the genetic material of three parents, with our MPs voting for the bill on Tuesday.

Now in the UK we also have a House of Lords, who also must approve the bill at a later date, and there’s no guarantee they will, but given the large majority of parliament members (382 to 182) it’s likely they will. It also has to be approved by the Human Fertilisation and Embryology Authority, a UK governmental organisation.

On Tuesday morning I was listening to Morning Call on Radio Scotland. It’s a fairly simple show, where people call in to give their opinions on any given subject. That, combined with the online reaction today, has had me and my colleagues thumping our foreheads against the desks repeatedly.

Buzzfeed has a great “Six Things You Should Know...” list that I won’t repeat here, but there are a few things we have to discuss …

 

Three Parent Babies is a Bit of a Stretch

Yes, this is a classic case of a catchy headline. The mitochondria, which you probably remember from high school biology, is essentially the battery of a cell. Long, long ago in our evolutionary past, back when we were simple collections of cells, mitochondria were simple single cell organisms capable of doing things our little cells weren’t. Namely powering things. So they were captured and made a part of larger cellular organism that was us. And the rest, as they say, is history.

But it’s because of this that mitochondria have slightly interesting and unique DNA, a separate part of our genome that codes for our mitochondria. Some organisms have managed to get rid of all of the mitochondrial DNA, and others have got weird mutations in there, we’ll come back to that later.

The important thing to note is that ‘three parent baby’ simply takes the mitochondrial DNA from one genome, and the rest of the DNA in the traditional method (for a given definition of ‘traditional’, in a test tube, under the stars, wearing leather, wearing lace . . . ) comes from the two parents.

 

A Gateway To Eugenics

One of the strangest comments I’ve heard in relation to this news is that it means we’re a step closer to eugenics. This is, in some ways, deeply insulting to the families of those who are suffering from mitochondrial diseases. To want to be free of disease does not equate to eugenics.

In humans, mitochondria are inherited directly from the mother. You’ve heard of Mitochondrial Eve? The reason we have her is because our mitochondrial DNA doesn’t get recombined and altered in the same way as the rest of our genome. Like the Y chromosome, it is an excellent way of doing forensic genetics. Both of them remain greatly unchanged throughout our evolutionary history, and we can track back to a conceptual Mitochondrial Eve and Y Chromosome Adam. However, I’ll point out that these aren’t real people. They’re simply the earliest ancestor we’re all related to – which changes as our population changes over time.

But it’s this phenomenon, the conservation of this DNA, that allows us to swap them out in this fashion. The DNA inside the mitochondria is so useless to the rest of the body they can be exchanged very easily. So you see, we’re still many, many years and innovations away from selecting the genes we want and engineering our babies. This procedure is feasible, and safe, because mitochondrial DNA is so protected, and usually inconsequential in a genome.

 

Why Do We Need It?

Because mitochondrial diseases are horrific things. The mitochondrial DNA is special, yes, separate from the rest of the DNA, yes. But it also mutates, as all DNA does, and it doesn’t have much of a way of repairing itself or realising that its damaging its body. Symptoms include Multiple Sclerosis style diseases, loss of eyesight, loss of hearing, dementia, neurological problems, an inability to exercise, diabetes, poor growth, heart disease, gastrointestinal disorders . . . and each one of these things are a SYMPTOM of the disease, not the disease itself.

We can eradicate this disease, easily, while maintaining a person’s right to reproduce. If you fear that because you’ve seen one too many B movies about Frankenstein . . . you just show me how much work I have to do.

 

 

Finally I have to say something about the “Science has gone too far” style comments, and “humans have evolved to their current state, we shouldn’t meddle”. In so many cases, comics can communicate more about science than any of my blogs. To those people I say . . .

Thag no! You go too far! 

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