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There has been a great deal of coverage this week of the new patent issued to genetic testing company 23andMe. U.S. Pat No. 8,543,339 is entitled “Gamete donor selection based on genetic calculations” and is directed to methods for predicting traits for a child based on the DNA of candidate parents, and selecting a preferred donor based at least in part on the prediction.
Some of the coverage (including an editorial in Genetics in Medicine) has suggested that the methods are “hugely ethically controversial” and “‘GATTICA’-like,” and could lead to a “design-your-own-baby DNA test” and “designer babies.” Another popular genetic genealogy blogger, Roberta Estes, also addressed the patent on her blog earlier this week (“23andMe Patents Technology for Designer Babies”).
23andMe preemptively addressed the patent in their blog the Spittoon (“A 23andMe Patent”), and stated that “[t]he company never pursued the concepts discussed in the patent beyond our Family Traits Inheritance Calculator, nor do [they] have any plans to do so.”
Too Much Hype?
The negative hype surrounding the patent, however, is based entirely on the misguided theory of genetic exceptionalism (the belief that genetic information is special and must therefore be treated differently from other types of medical information), and is unwarranted.
Here is a brief summary of my hypothesis, which I’ll get into in more detail below:
- People have been screening possible gamete donors for decades based on things like religion, ethnicity, education, height, weight, eye color, hair color, age, and personal/family medical history, among other things (notably, several of these things are proxies for genotype, and some even work better than genotyping);
- The difference between using the traditional traits/characteristics listed above for donor screening and the methods described in the 23andMe patent is that the patent involves the use of DNA to screen donors: accordingly, the outrage about this patent is based on genetic exceptionalism; and
- Genetic exceptionalism lends itself very easily to government regulation, and is therefore potentially unfavorable for anyone opposed to genetic paternalism (including, presumably, genetic genealogists).
#1 – Selecting A Donor Without DNA
Although some may disagree with points #2 and 3 above, point #1 is indisputable. People have been screening potential donors for at least 50-60 years based on one or more of the factors listed above. Things such as personal and family health history have a very strong genetic component, and in almost every way are better predictors of health in offspring. For better and for worse, DNA has not turned out to be the strong predictor scientists thought it would be.
And even before gamete donation, there was the simple selection of mate based on appearances and behavior, which can be very closely tied to genotype.
Regardless, there is no doubt that donors have been screened for decades. However, I’ve never heard anyone suggest that donors should not be screened, or that there should be regulation of donor selection to prevent screening based on certain traits. Indeed, none of the coverage has suggested that any screening be stopped, other than DNA-based screening. At best, a few of the better articles have mentioned in passing that non-DNA factors are routinely used for donor selection.
#2 – The Myth of Genetic Exceptionalism
The 23andMe patent describes methods of using genotype (DNA) to predict the possible traits of a child and thus allows the selection of a particular donor based on the “best odds.” How is that process different from selecting a donor with the highest level of education and hoping that it corresponds to intelligence in the child? Or selecting a tall donor with dark hair in the hopes that the child will be tall with dark hair? Or selecting a thin donor in hopes that the child will be thin?
The difference is likely only that many people believe that DNA is different or special, that selecting for an “A” at position rs123456 is somehow different than selecting “dark hair” or “175 lbs.”
There is also a knee-jerk reaction that any screening or selection based on DNA is “eugenics,” although people have been selecting mates (and later, donors) based on the outward expression of DNA for millennia (facial features, hair color, eye color, height, weight, etc…). The fear of eugenics is a good and necessary fear, but calling any selection or screening based on DNA eugenics is crying wolf.
#3 – The Danger of Genetic Exceptionalism
Unfortunately, genetic exceptionalism and genetic paternalism go hand-in-hand. Many, including many bioethicists, believe that since DNA is “special” it should be regulated in order to protect the consumer. There should be, some argue, a physician or geneticist that can guide the consumer through the process. Others argue that there should be no ability whatsoever to take certain DNA tests. The theory that consumers need a “protector” from their DNA is what I call “genetic paternalism.” In my home state of New York, for example, I am unable to spit my DNA into a tube for testing without a physician to order the test.
Much of the discussion of potential regulation of direct-to-consumer tests such as those offered by 23andMe, Family Tree DNA, and Ancestry.com is framed in terms of “protecting” the consumer:
- “Current regulatory controversy focuses on potential harms associated with direct-to-consumer (DTC) marketing of nutrigenetic tests and especially the need to protect consumers from unreliable tests, false claims and unproven dietary supplements.” (here)
- “Marketing genetic tests directly to consumers can increase the risk of a test because a patient may make a decision that adversely affects their health, such as stopping or changing the dose of a medication or continuing an unhealthy lifestyle, without the intervention of a learned intermediary.” (here)
Not surprisingly, here has been no call for regulation of traditional donor screening, but there has been plenty of call during the last week for regulation of genetic screening.
And The Scientific Limitations
There are also some serious scientific limitations to the concerns. At Wired, personal genomics aficionado Daniel MacArthur provided the following:
Geneticist Daniel MacArthur of Massachusetts General Hospital said he’s not especially concerned about moral objections to selecting offspring traits with the type of technology described in the patent, but he thinks it’s important to be realistic about what’s even possible.
Indeed, in 2009 I wrote a paper entitled “The Potential Impact of Preimplantation Genetic Diagnosis on Discrimination of the Disabled: Analysis of Mitigating Factors,” in which I argue that although parents will eventually have the ability to screen embryos based on thousands of tested traits, the science simply prevents preimplantation screening based on more than a tiny handful of traits.
For example, if I only have a small number of viable embryos that I can screen, there will only a very limited number of possible combinations. I would need hundreds or thousands of embryos to positively select for a large number of traits. The paper provides an example of a three-trait cross, in which just 1 of 16 embryos will statistically satisfy the requirements for all three traits. However, fertility centers only harvest an average of 6 to 15 eggs for in vitro fertilization.
The 23andMe patent describes a method for calculating the possible traits of a child and lets the user select a donor based on those calculations. In my opinion, the only difference between this method and using education or health history to screen donors is the involvement of DNA. How you come out on this issue is likely a strong predictor, I would imagine, of your opinion of genetic exceptionalism.