On BioScience and Life and Such

Posts Tagged ‘genetic testing’

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Now this is why we need genetic counselors

In Uncategorized on April 25, 2008 at 12:00 pm

After reading “Living at risk: Concealing risk and Preserving Hope“, which was an eye-opening experience, I am ready to argue against myself and the arguments in my previous post “Now why do we need genetic counselors ?”.

In this post I predicted that genetic counselors may soon be obsolete because nobody cares about low-risk alleles. In addition I argued that information on high-risk alleles is better managed by physicians.

The not caring bit is still true (unfortunately) as far as I know, but after reading the above mentioned paper, I need to modify my opinion on high risk tests. High risk tests in this context, are tests that if positive, means developing disease in the near future. Testing for Huntington disease is a model example of such tests since:

“Penetrance, the likelihood of showing symptoms of the disease if the associated genetic mutation is present, is virtually 100%.”

Thus, this is a clear medical case and a physician should be able to give adequate counsel to the patient. But, the issues a practitioner would face are so much more than medicine alone and recommendations for counseling goes wider than what is expected of a primary care physician:

Nearly every participant with children experienced terrible difficulty in talking to their children about their risk, even when the children were grown. We infer from this difficulty that practitioners could, and should, find ways to help people at risk develop plans for educating their children at an appropriate age. We envision such plans to be developmentally based, geared to answering questions at the child’s level, as well as being persistent and gradual in the presentation of the issues of importance.

This to me, sounds like genetic counseling. Further arguments for genetic counseling comes from the recommendations to the clinicians:

Clinicians also need to reflect on their own beliefs and biases about genetic testing, and to examine the extent to which those beliefs and biases present themselves in their care for people at risk for HD. Primary care health professionals need to be cognizant of the fact that just because a test can be done does not mean that it should be done. What these men and women are telling us is that it is not safe to assume that genetic testing for incurable diseases will necessarily provide information that is wanted, or needed, by those at risk and that testing may have a significant negative impact on the lives of their patients.

Objectively reflecting on genetic testing as well as telling the patient that it may actually be wise not to get tested, are probably things a genetic counselor would do better than the primary care physician.

So, the conclusion must be: I was wrong, we need genetic counselors. Reading “Living at risk: Concealing risk and Preserving Hope” will tell you this. In adition it will teach you that 80-85 % of at risk individuals elects not to undertake predictive genetic testing. They do so to survive since a lack of hope can be devastating:

Something that my uncle said, that I think really stuck with me, is he wrote a suicide note. He said that there’s such a big difference between living with hope and living with knowledge. And that he would take the living with hope any day. And so he really did not think we needed to know, one way or another.

…………and, proper counseling (not only genetic) may be a help for people in handling their life at risk since:

It is noteworthy that several participants said the interview for this study was their first opportunity to talk about the emotional side of HD, despite their years of experience with neurological, cognitive, and psychomotor testing …………… We think that unstructured interviews might actually change the views and actions of the participants with respect to their careful concealment of risk and their preservation of hope.

This is probably true. Regardless of the extent of counseling, it seems to me that genetic counseling for these patients and their family members is a good starting point.

The final take home message must be that not testing for a condition has significant value, especially when treatment options are scarce or non-existent.

Hope is sometimes a life saver. Knowledge on the other hand, can put peoples lives in ruins. Use this as a guiding light if you will, – I know I am going to.

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Now why do we need genetic counselors ?

In Uncategorized on April 17, 2008 at 11:49 am

According to the National Society of Genetic Counselors, genetic counseling is:

“the process of helping people understand and adapt to the medical, psychological and familial implications of genetic contributions to disease.”

But a commentary in Science Magazine indicates that these admirable goals are unachievable. It turns out that patients given genetic information on predisposition to disease don’t really care. Consequently, they are unlikely to do any changes to their lifestyle based on the test-results. Behavioral epidemiologist Colleen McBride and human geneticist Lawrence Brody are quoted saying:

“They’re not having big emotional
responses”

And subsequently the author concludes that:

“Behavioral specialists have shifted from
worrying about the devastating effects of
learning about these new genetic risks to
wondering whether the information will
make any impression at all.”

The REVEAL study (by way of Genomeboy) modifies the picture slightly on the willingness to change lifestyle based on test results from APOE, but confirms the lack of distress or anxiety resulting from test results. The REVEAL study was designed to measure:

  • Who seeks genetic counseling and why
  • How APOE disclosure affects risk perceptions
  • The psychological impact of genetic risk assessment
  • How risk information affects participants’ subsequent health and insurance behaviors.

Where the findings included:

  • Disclosing APOE status and its association with Alzheimer’s risk to participants did not result in a significant increase in distress or depression.
  • Participants who discovered they had the high risk APOE e4 allele proved more likely to be proactive in changing their lifestyles and planning for long term care.
  • A majority of participants reported that REVEAL had made a positive impact on their lives (67% positive vs. 17% negative).
  • Participants were more likely to report lower, rather than higher, anxiety about Alzheimer’s disease as a result of being tested (43% lower vs. 11% higher)

Thus, it seems the fear of damage caused by genetic test results is unwarranted or at least highly exaggerated. So, the question is: is there still a need for genetic counselors to ease distress ?

Yes one might answer, since genetic counseling is still needed to interpret the result. … – But,

In addition to the well known test for BRCA1, genetic tests are increasingly emerging that will give clear cut answers. Additional examples are colon cancer and lung cancer if you are a smoker. Understanding the technology behind the test becomes less important when test-results leads to unambiguous recommendations. No need to know what a SNP is if having it gives you a disease risk of 80-90 %. Thus, counseling to explain the problem of uncertain statistical probabilities may soon be obsolete.

If the risk turns out to be less than 80-90 % (and consequently less reliable for a physician as a proper pre-diagnostic test), according to the piece from Science magazine: it looks like nobody will care. If this is the case, genetic counseling for tests associated with medium to low risk becomes superfluous.

As an alternative then, I would suggest that genetic counselors turn their focus towards relieving group damages from genetic testing. That may be the life saver for a group of professionals once thought to have a bright future, now facing a dim/boring one.

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Tests that make me sad (updated)

In Uncategorized on February 29, 2008 at 10:46 am

In a previous post (“Clarifying misuse of Science“) I expressed concerns over Prenatal testing for familial hypercholesterolemia. Now it seems I should have included two more (and in my mind, – more controversial) tests approved in the UK for preimplantation testing preceding IVF. These are tests for breast cancer (BRCA1) and early onset Alzheimer.

Especially the case of BRCA1 worries me. True, the prevention (mastectomy) is a horrible ordeal for the patient, but is this sufficient grounds for excluding eggs for IVF ? Can’t you live a reasonably happy and normal life after such a procedure (see breast reconstruction) ?

Why haven’t there been more fuzz around this ? Is everyone going to be using prestested eggs in IVF now ? And what are the limits on acceptable tests, will testing for athletic performance become an exclusion criterion soon ?

I must have been naive to so strongly oppose the slippery slope argument in genetic testing discussions up until now. I wish we could restrain ourselves a bit more, but fear that we can’t.

The solution is to come up with treatments for most of these conditions (although treating athletic performance may constitute a problem in terms of the number of people needing treatment as well as treatment alternatives…..).

Treatment alternatives need to appear soon if we’re to avoid the brave new world future that critics of the genetics era have been promoting …..

The “find a cure” process however, is not going to be fast and in the 10-25 years to follow, those concerned couples that have the option of BRCA1 and Alzheimer testing will most likely not take the chance that a treatment will be found in time for their child to be cured…….., – and opt for the safer pretested egg and IVF.

Seeing that the slope is becoming slippery I have decided not to argue for genetic testing any further, and if this trend continues, – argue against, at least until treatment options appear (the next 25? years) or a sensible limit for testing is drawn (right now, – please).

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Tests that make me sad

In Uncategorized on January 7, 2008 at 9:45 am

In a previous post (“Clarifying misuse of Science“) I expressed concerns over Prenatal testing for familial hypercholesterolemia. Now it seems I should have included two more (and in my mind, – more controversial) tests approved in the UK for preimplantation testing preceding IVF. These are tests for breast cancer (BRCA1) and early onset Alzheimer.

I must have been naive to oppose the slippery slope argument in genetic testing discussions up until now. I wish we could restrain ourselves a bit more, but fear that we can’t. Why haven’t there been more fuzz around this ? Is everyone going to switch to using prestested eggs in IVF now ?

A (tricky) solution is to come up with treatments for most of these conditions, – looks like that needs to happen fast if we’re to avoid the brave new world future that critics of the genetics era have been promoting …..

The “find a cure” process of course, is not going to be fast and in the 10-25 years to follow, those concerned couples that have this option will most likely not take the chance that a treatment will be found in time for their child to be cured, and opt for the safer pretested egg and IVF.