Saturday, December 15, 2007

Screening for Hypercholesterolaemia

This story in the Times and this one in the Guardian report about HFEA's decision to permit a couple to screen their embyros for familial hypercholesterolaemia (FH), a condition that increases the risk of heart attack and can result in death during childhood.

Here are a few excerpts from the two stories:

From the Guardian:

A couple who have a milder form of the disorder are seeking permission to have their embryos screened by Paul Serhal, of University College hospital, London, according to the Times.

They have a five-year-old daughter, who was born with the serious homozygous form of FH and fear any other children they have could also be affected.

The decision may reignite controversy over parents' rights to create "designer babies", as the procedure may also identify a milder form of the disease that is affected by lifestyle and can be treated with drugs.

"This obnoxious disease can cause cardiovascular accidents at a very early age," Serhal said. "Some people would think twice about using embryos that they know have a risky gene, and others would say you shouldn't screen out a condition that can be managed..."

There are two forms of FH. The mild - or heterozygous - form affects about one in 400 people but can be controlled with cholesterol-lowering drugs. About one in 250,000 people inherits two defective copies of the gene and develops the more serious of homozygous FH. Sufferers can experience angina by the age of six.

An HFEA spokeswoman indicated it may only permit screening for the more serious form of the disease.

And from the Times:

Critics argue that the test will allow couples to destroy embryos that would have had a good chance of becoming children with fulfilling and reasonably healthy lives.

The test will also create an unprecedented moral dilemma for some couples, as it could show that they have produced no embryos completely unaffected by the disease. This would force them to decide whether to implant embryos that they know have a genetic risk of premature heart disease and death, or to throw them away and deny them a chance of life.

It's very unfortunate that both stories refer to screening for FH as "designer babies" (the Times article is titled "Designer baby fear over heart gene test"). This kind of sensationalist journalism only impairs informed, reflective debate on what is a very serious issue. Rather than being an issue of a parent's right to create "designer babies", the right at issue here is the right to minimize the risk of death and disease for one's offspring. Far from being trivial, this is a fundamental right and freedom.

Undergoing IVF and screening the embryos before making a decision of which, if any, of the embryos to implant does not mean a parent is creating "designer babies". Rather, these parents face the following decision: (1) do they implant embryos that have the gene for the disorder or (2) those embryos that don't have the gene. Or, if all the embryos have the gene, (3) do the parents decide not to implant any of those embryos. Denying the parents the opportunity to screen simply means the decision the parents face becomes: do you opt for reproduction when you know there is a high probability you will have a child with this disorder? None of these embryos would even exist (and thus they would not be discarded) if parents are not permitted to screen as I assume the parents would only opt for IVF if they could screen for the gene in the first place. So prohibiting screening for FH will not save embryos that would otherwise be discarded.

If one is tempted to find such reasoning persausive then just look at things this way: for those parents that decide not to have another child, because they don't want to risk having a child with FH, the decision to prohibit the screening of embryos for FH has closed off the only chance they [i.e. these potential people] have of coming into existence. But of course there is not a high probability that any embryo implanted will result in a live birth anyways. So this line of reasoning is faulty in many respects.

Furthermore, I was puzzled about the way the Times described the decision parents may face if they discover that all their embryos have this gene. These parents must decide whether they want any of the embryos to be implanted. But this is hardly an "unprecedented moral dilemma". Such a decision shares many parallels with the decisions parents face when them decide to have an abortion after a prenatal screen detects an abnormality (though one could argue that the decision to abort is an even tougher moral dilemma).

It is unfortunate that, when it comes to something as important as a parent's reproductive freedom, the onus is on the parents to convince HFEA that their interest in having the test is not iniquitous. Whereas the onus should really be on the government to show that an intrusion on a parent's reproductive freedom is justifiable. Add to this the fact that journalists often impair, rather than enhance the quality of, public debate on such issues by invoking sensationalist sentiments like "designer babies" and the prospect of deliberative democracy looks unlikely. This is why I believe it is better to view such screening technologies as falling within the scope of reproductive freedom and thus a "constitutional essential". To limit this freedom we must have demonstrable evidence that a pressing and substantial harm will likely occur to an identifiable group or individual. And this simply does not happen in the case of permitting parents who undergo IVF to screen embryos for a genetic disease like FH.