It’s only natural – let’s make it better
If we can improve, we should.
A bad few weeks, then, for misbehaving chromosomes. First, a Hollywood star draws attention to their errant ways. Next, laboratory scientists find a way to cut them out of the picture. And then, just a day later, camera-wielding researchers announce they can spot the miscreants a mile off.
We can only hope that the IVF pioneer Robert Edwards was given a special preview of the latter research before he died last month. IVF has always been criticised for raising too much hope and too much cash. A round can cost a couple £10,000 yet the chance of it ending in a live birth in the UK is still only 26 per cent. Now, however, a relatively straightforward technique of watching for misbehaving chromosomes might rocket that success rate up to 80 per cent.
The technique sidelines the entirely natural shortcomings of our chromosomes – the packages of DNA inside every cell nucleus. Even in normal circumstances, roughly half of all fertilised eggs carry some kind of abnormality. This predisposes the embryo to problems and usually ends the pregnancy before it begins. But in the sealed glass box where an IVF embryo begins, those chromosomal problems expose themselves in a way that allows doctors to choose the one with the best chance of survival.
The four-day process of turning into a blastocyst, the ball of cells that would normally be implanted in the mother’s womb, takes about six hours longer if there is a chromosomal problem. Using time-lapse photography, you can see which embryos have issues and which are ideal for implantation. The simplicity of the technique would no doubt have brought a smile to Edwards’s face.
He would have been less happy about this month’s press surrounding the breakthrough in human cloning. Scare stories abounded – the Daily Mail went with the headline “New spectre of cloned babies” – and much was made of how it is the same technique as produced Dolly the Sheep, who died prematurely due to abnormalities induced by the cloning process.
The breakthrough is not aimed at making new human beings, however: the idea is to make ill human beings feel like new. First, take a cell from the patient and fuse it with a human egg cell that has had its genetic information removed. The egg then develops into a source of embryonic stem cells that can be turned into bone, blood, heart or liver tissue, or anything else that might be necessary for the patient’s return to health. Such tissues would not be rejected by the immune system, because they would be a perfect match for the patient’s biology.
Until now, the only hope of doing this has been to use chemicals to turn back the clock on a cell, so that it rewinds to the state where it could become any kind of tissue. This chemical approach, however, creates a high chance of inducing abnormalities that elevate the risk of subsequent problems – cancer, for instance.
Cancer comes naturally, too: it has been our constant companion throughout human history. However, this natural phenomenon also suffered a setback this month. The actress Angelina Jolie announced that she had undergone a double mastectomy to counter an inherited genetic fault (on chromosome 17, but there’s a related fault that can appear on chromosome 13) that would almost certainly give her breast cancer. There’s a very strong chance the surgery will have saved her from a premature death, and her courageous broadcasting of the news will put many other women on the path to saving themselves. Take that, nature.