Genetic Testing: Do you really want to know your genome?

September 19, 2012Carole 1 Comment »

If you could know the DNA sequence of your entire genome- the instructions that make you who you are–would you want to know it? What if knowing that sequence could help your doctor identify drugs that will work best for you and avoid drugs that are unlikely to work or cause severe side effects for you? What if your genome sequence showed that you are at risk for developing a disease and this advance knowledge could allow you to adjust your lifestyle and avoid developing the disease? What if, on the other hand, you found out that you were highly likely to develop a disease that has no treatment and no cure. Do you still want to know? Once your genome is part of your medical record, insurance companies can request this info to decide if you are a poor risk for life insurance. Do you want insurance companies or other parties, like your employer, to know your risk of diseases?

NPR recently aired two fascinating reports that deal with these questions:

Scientists see upside and downside of sequencing their own genes  and As genetic sequencng spreads, excitement, worry grow.

What does this have to do with IVF? Well, actually, with the advances in genetic sequencing of the embryonic genome available through pre-implantation genetic testing, IVF couples are already facing those issues.

To screen, but not tell: the ethical dilemma of non-disclosing medical care

The ethics of medical care is grounded in the concepts of transparency and informed consent, but non-disclosing genetic screening upends those bedrock principles and raises numerous ethical questions.

Consider this hypothetical case. A young couple, Mark and Mary,  request IVF with PGD for Huntington’s Disease. Huntington’s Disease is a late onset genetic disease which has no treatment and no cure and which invariably  results in a slow agonizing decline with increasing loss of both physical and mental faculties. The genetic test for Huntington’s is inexpensive and accurate but many individuals choose not to know their status, because they are not willing to live with the knowledge that they are doomed to this slow cruel demise.

In our scenario, Mark and Mary want their IVF embryos biopsied and genetically testing before the transfer. Based on that report, they want only normal unaffected embryos transferred back to Mary. Mark has a family member who was recently diagnosed with HD and he has been informed that he, too, is at risk for the disease. Mark is adamant that he does not want to be tested because he simply does not want to know if he has the HD gene, as there is no treatment and no cure.  He is equally adamant that he does not want to pass this dread genetic disease to the next generation. The IVF center agrees to do IVF with PGD and agree to only transfer normal embryos. The genetic testing lab will issue a NON-disclosing report format which will only disclose that each embryo is either “suitable” for transfer or “not suitable” for transfer, which provides no genetic information, per se. Only “suitable” embryos will be transferred. The “not suitable” embryo category can also include embryos for which the test is inconclusive due to assay/biopsy problems or even embryos that simply failed to grow in culture. The couple will decide in advance the maximum number of embryos they would prefer to transfer and this number or less, will be transferred, depending on the number of embryos that are “suitable” for transfer.

The couple has specifically requested that NONE  of the IVF report data be shared with them. Typically, an IVF report would disclose how many eggs were retrieved from the ovaries, how many eggs were normally fertilized, the number of fertilized eggs that cleaved and the number of embryos that are progressing normally to either day 3 or day 5 of in vitro culture, when they are transferred to the uterus. The requirement of non-disclosure dictates that none of this information is shared, because of what can be deduced about the likelihood of harboring the HD gene. If the couple knows how many eggs are fertilized, and how many embryos are suitable for transfer, then they can infer whether they have the disease or not, depending on expected genetic ratios for HD. For example, if they have a large number of embryos, yet three-quarters of them are “not suitable”, that strongly suggests the most of the embryos carry the HD gene and Mark has the HD gene.

Furthermore, the couple refuses cryopreservation of excess embryos because if they are informed that no embryos were available for freezing, they could infer that the embryos carried the HD gene. If the patient has only normal embryos, those in excess of the number to be transferred will be destroyed. Even the happy news that all the embryos are normal can not be shared because were this an option, and the health care team says nothing, than the couple could conclude that at least some of the embryos were abnormal, which would confirm genetic disease in the couple.

Here is perhaps the most problematic outcome, what if all the embryos are abnormal and none can be transferred? The couple could be told that all their embryos are not suitable for transfer, confirming either complete technical incompetence, or that these embryos carry the HD gene. To avoid any information which might indicate the genetic state of the husband, the couple requests no information regarding the suitability of embryos for transfer and that the IVF team schedule an embryo transfer regardless of the genetics report. In this case, the health care team would perform a transfer procedure but with an empty catheter.

Questions that arise:

The health care team has medical knowledge that they are required to conceal from their patients. Under what circumstances is this ethical? Can a special consent form outlining clearly what will and will not be disclosed be used and is that sufficient to perform this ethically?

If the patient’s insurance provider is billed for a transfer, even though the transfer is a “mock transfer” without an embryo, would that constitute insurance fraud? Supplies are used, professional services are provided but the essential element for the success of the procedure, the embryo, is not included in the process so it is not performed with the expectation of causing a pregnancy.

Some couples refuse embryo cryopreservation of excess embryos because they are concerned that failure to have any extra embryos to freeze could indicate that they have the disease, so perfectly health embryos may be discarded simply to preserve the non-disclosure status of the patient.

Who is the patient in this scenario? IVF treatment is usually considered a treatment of the couple. But in this case, Mary is not the person at risk for HD but is required to undertake most of the interventions and all of the risk of the IVF procedures. Especially when one considers that a simple test might rule out the need for IVF with PGD all together. After the transfer, if Mary changes her mind and wants to know whether the transfer catheter contained an embryo, is it ethical to withhold that information from her? Does the health care provider’s duty to the wife or the husband, especially when their wishes for non-disclosure diverge?

Is the health care team ethically obligated to refuse more than one IVF attempt in advance to prevent the scenario of repeated mock transfers?

If all imaginable potential scenarios are explored with the couple in advance and advance informed consent is given for each possible outcome, is it ethical to proceed with non-disclosing medical treatment? If unexpected scenarios arise and the health care team or the physician is expected to make a decision without the couples input, is this ethical to do so if he is not their medical executor? Can a third party be asked to arbitrate if unexpected situations arise that have not been covered in the informed consent?

Generally speaking, I am always in favor of more patient information, rather than less, more choice, rather than less choice. But I would be fooling myself if I didn’t admit a some personal discomfort from providing “non-disclosure” services to patients because keeping patients in the dark feels so wrong. On the other hand, is a “Right Not to Know” any less compelling then a “Right to Know”? What do you think?

More on this topic from the Huntington’s Disease Society of America website, an article called, Making Babies: Having families the HD way.

© 2012, Carole. All rights reserved.

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