Fresh on the heels of the launch of the deCODE BreastCancer genetic test last week, Dr. Arthur Caplan, renowned director of the University of Pennsylvania Center for Bioethics, said in an article for MSNBC.com that breast cancer gene tests are not worth the price.
If you are worried about your risk of getting the disease, or are thinking about getting a genetic test done for any other reason, talk with your doctor or a genetic counselor who can determine whether your family history justifies the expense. You may be surprised to find that you can make changes in lifestyle and monitoring your own health that can reduce your risk without testing.
Dr. Caplan even goes so far as to accuse genetic testing companies of corporate greed which, given the current economic environment in the U.S., is bound to send shivers down their spine.
With respect to deCODE’s breast cancer genetic test, it examines seven single nucleotide polymorphisms* (SNPs) that are purportedly involved in 60 percent of all breast cancers. Results from the test are given as personal lifetime relatively risk compared to the general population (specifically people of European descent). Other risk factors such as family history, pregnancy history, etc. are not taken into consideration when calculating a deCODE BreastCancer genetic test taker’s risk.
deCODE’s Chief Scientific Officer, Dr. Jeff Gulcher, responded to Dr. Caplan on its blog, deCODE You (a member of the DNA Network) and drew analogies between the BreastCancer genetic test and LDL-cholesterol tests. Anyone who is identified to be at higher risk of breast cancer (or in the analogy, high cholesterol leading to cardiovascular disease) would benefit from greater vigilance, more intensive screening, and possibly, preventive therapy.
Another DNA Network member, Dr. Steve Murphy at Gene Sherpas calls the deCODE BreastCancer test “hype.” Cancer Research UK also believes that “it’s too early for a test of this kind to be released to the general public.” Dr. Len Lichtenfeld of the American Cancer Society does not believe the test will “advance our cause in the fight to reduce deaths from cancer in a meaningful, evidence-based and scientifically accurate way.”
Speaking of cost, though,it seems that 23andMe customers get the better deal because six of the seven SNPs (rs4415084 was on the v1 chip but not on the v2 chip) examined in the deCODE BreastCancer genetic test are included on version 2 of the 23andMe gene chip (I checked using SNPedia) not to mention the other nearly 600,000 SNPs included in the 23andMe report. A 23andMe DNA test costs $399 while a deCODE BreastCancer genetic test costs $1,625.
deCODE’s test offers other bits and fancy algorithms for calculating risk to justify the price. But customers should be aware that there is more than one way to get the genetic data they desire. And that data’s worth can be hard to price.
*See the list of SNPs in this sample report (pdf).
Hsien-Hsien Lei (pron. shen-shen lay) is a PhD-trained epidemiologist and biotech consultant. She blogs regularly at Eye on DNA, where this post first appeared. She is a consultant to DNA Direct, a genetic testing company.
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Tests done for clinical genetic purposes. Genetic tests may be done for diverse purposes pertaining to clinical genetics, including the diagnosis of genetic disease in children and adults; the identification of future disease risks; the prediction of drug responses; and the detection of risks of disease to future children.
The DNA theory of cancer (a limited number of genes causes cancer, so cancers are more or less the same) hasn’t yet produced the types of breakthroughs we all want. Most everyone in cancer research seems to have centered their attention on DNA being the culprit.
It would be expected that after spending so many years of pursuing this one angle, and the numerous links that have been made, this should have lead to more progress than is presently observed. There is always a cytogenetic and a biochemical individuality in every cancer.
Growing evidence suggests that gene-based prediction is not stable and little is known about the prediction power of a gene expression profile as compared to well-known clinical and pathologic predictors. Cancer prognosis from a handful of genetic mutations that drive a cell into uncontrolled growth, has failed many aspects of cancer.
Genomics are far too limited in scope to encompass the vagaries and complexities of human cancer biology.
I recently blogged on this issue, too, over at my Business Ethics Blog. For me, this is a commercial issue, a question of business ethics that Caplan’s bioethical spotlight might not illuminate well. Really, here, genetic testing is a product, and ought to be evaluated as such, rather than being evaluated (only) as a clinical intervention:
Genetic Testing: Ethical to Market a Not-Very-Useful Product?