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Perspective from a US physician: Pre-implantation genetic diagnosis (or PGD, what you described as 'selective IVF') is not cheap. It costs upwards of US$100,000 and no commercial or government insurance will cover it. Genetic screening is also not cheap. An exome (essentially looks at all ~22,000 known exons, or the genes that directly contribute to protein formation) costs US$6,000 - $8,000 and most insurances will fight tooth and nail not to have to cover it even when it is ordered by a geneticist. You might think "but there are much cheaper genetic tests besides an exome" which is true, but remember we are talking about rare diseases. Exome testing is still imperfect but it is essentially the only realistic option if your goal is to rule out as many known genetic diseases as possible, or if you know there is a high pretest probability of a genetic disease but less exhaustive testing was negative or inconclusive. Actually, current PGD doesn't use exome testing but much more selective testing often based on the parents. One technique is FISH which can essentially only tell you if there are any "large" genetic abnormalities, like (micro-) duplications or deletions, which are large relative to, say, a point mutation. As an example, FISH testing would not reveal cystic fibrosis. The other is PCR, which is currently the technological limit for PGD testing because of the small number of cells and minimal amount of genetic material available for testing. There are several PCR assays available for specific conditions in the setting of PGD, which is where the parents fit in. We will probably see more and more assays becoming available, but it is unlikely that anything resembling an exome will be feasible for PGD in the foreseeable future. Disclaimer: I am not a geneticist or reproductive specialist. If you can find sources by physicians in these fields, I would defer to them. |