Google Founder's Blog Delves into Personal Health

Credit: Google

In his new personal blog, started yesterday, famed Google founder and multibillionaire Sergey Brin delves immediately into a deeply personal subject: his genetic risk for Parkinson's disease. Brin, whose mother suffers from Parkinson's, learned that he carries a mutation linked to increased risk of the disease after being screened by 23andMe, a personal-genomics startup cofounded by his wife, Anne Wojcicki.

23andMe's brand of direct-to-consumer testing has garnered criticism from the genomics community for going on the market before scientists have had a chance to assess whether such tests can actually help, or would possibly hinder, an individual's health. (If someone finds out that she is at greater risk for type 2 diabetes, for example, she may adopt a fatalistic attitude, eating junk food and not exercising.) Critics are also concerned that the general public won't be able to understand the subtleties of the test: 23andMe's service identifies genetic variations that may increase an individual's risk of disease, but that does not mean that the carrier will ever get it. (A review in our current issue argues against this point of view.)

While Brin doesn't discuss why he decided to go public with his results, perhaps he wants to use his role as an Internet celebrity and, in some sense, experimental test subject to better educate the public. His post nicely outlines the limitations of personal-genomics testing and discusses what an individual can do once he learns his own risks, even for a disease like Parkinson's, with few proven preventative interventions. Better public understanding of these issues is going to be crucial as personal genomics makes its way into medical care, be it through companies like 23andMe or other venues. (Cynical readers, of course, might see an alternative motive: an attempt to drum up interest in his wife's company's service, in which Google has invested.)

From Brin's post:

...The exact implications of this are not entirely clear. Early studies tend to have small samples with various selection biases. Nonetheless it is clear that I have a markedly higher chance of developing Parkinson's in my lifetime than the average person. In fact, it is somewhere between 20% to 80% depending on the study and how you measure. At the same time, research into LRRK2 looks intriguing (both for LRRK2 carriers and potentially for others).

This leaves me in a rather unique position. I know early in my life something I am substantially predisposed to. I now have the opportunity to adjust my life to reduce those odds (e.g. there is evidence that exercise may be protective against Parkinson's). I also have the opportunity to perform and support research into this disease long before it may affect me. And, regardless of my own health it can help my family members as well as others.

I feel fortunate to be in this position. Until the fountain of youth is discovered, all of us will have some conditions in our old age only we don't know what they will be. I have a better guess than almost anyone else for what ills may be mine -- and I have decades to prepare for it.

In an article that I wrote for Tech Review two years ago on the study linking this genetic variation to Parkinson's disease in Ashkenazi Jews, scientists speculated on future clinical testing. (Brin is of Jewish descent.)

While gene testing for diseases that have no known cure, such as Parkinson's, is controversial, Laurie J. Ozelius, a molecular geneticist at Albert Einstein College of Medicine of Yeshiva University in the Bronx, who was involved in the research, says testing still could have some advantages. "People who come to the doctor [with symptoms of Parkinson's] already have a lot of degeneration. Now we can look at [earlier] stages of the disease," she says. "If we find treatments that slow the disease, it's better to identify a gene carrier so we can start the treatment earlier."

Susan B. Bressman, senior investigator of the report and a neurologist at Einstein, says that having a group with a known risk for Parkinson's will aid in future studies of the disorder. Because not everyone with the mutation will go on to develop the disease, scientists can try to identify the genetic or environmental factors that put some people at greater risk. Scientists could also test potential neuroprotective drugs in this group much more efficiently than in a general population.

23andMe Sharply Cuts Cost of Genome Analysis

For about the cost of a Sony PlayStation 3, you can now order a genome-wide scan of your DNA. 23andMe, a California-based personal-genomics startup, backed in part by Google, announced a dramatic cut in price today (from $999 to $399) for its genome analysis service. Customers who order the service send in a spit sample and receive a genetic analysis that includes predictions of their risk of developing various diseases, evaluations of other traits, and ancestry information; customers can even opt to compare their genomes with those of others. The company's two main competitors, Navigenics and Decode, offer similar services for $1,000 to $2,500.

According to an article from the Associated Press,

[Company founder Linda] Avey says one inspiration for the company's new pricing came from the iPod and iPhone, which sold for a similar amount in their early incarnations. The company hopes that consumers will start to see personal gene scans as similarly accessible technology with both serious medical value and gee-whiz appeal.

A press release from 23andMe says the price cut is enabled by improvements in genome analysis technology. The company uses gene microarrays made by Illumina, which have also been quickly dropping in price.

However, others speculate that 23andMe's price cut was fueled by an attempt to remedy lower-than-expected sales. Perhaps tellingly, the company has not yet revealed how many customers have subscribed to its service.

Another personal-genomics startup in Cambridge, MA, Knome, also expects to announce price cuts soon. Knome's service sequences and analyzes the entire genome, rather than specific areas, as 23andMe's does. As a consequence, it currently costs $350,000.

Personal-Genomics Companies Get California License

After sending cease-and-desist letters to a number of companies offering personal-genomics services directly to consumers, the state of California appears to have made peace with at least two of them--Navigenics and 23andMe. Both received licenses this week allowing them to continue to do business in California.

The letters, sent in June by the California Department of Public Health, outlined two main state regulations: laboratories performing tests must be clinically licensed, and a physician's order is required for all clinical tests. (For more on the state's action, see "Genetic Testing for Consumers Scrutinized.")

According to an article published Tuesday in the New York Times,

The companies had argued that they were not offering medical testing but rather personal genetic information services, and that consumers had a right to information from their own DNA. The companies also said they did not need a license because the actual testing of the DNA samples was being done by outside laboratories that did have licenses.

But the two companies do their own interpretation of the raw genetic data. Now, after reviewing the procedures used by the companies, the state is satisfied that the companies' interpretation is based on the scientific literature, Ms. Billingsley [a senior official in the California public health department] said.

Ms. Billingsley said the companies also satisfied the requirement for a doctor to be involved. Navigenics already was paying a physician to review customer orders and now it appears that 23andMe might be doing something similar.

It's not yet clear what this latest development portends for future regulatory debates, especially at the federal level; few federal regulations for these types of tests exist. As their popularity grows, scientists, regulators, and entrepreneurs will need to grapple with the central question of how to define this new breed of medical information, which falls short of being a diagnostic tool and, unlike risk factors such as cholesterol level and blood pressure, is deeply personal and ultimately immutable.

For more on regulation of direct-to-consumer genetic testing, check out the review "Personal Genomics: Access Denied?" in the September issue of Technology Review.

Genetic Tests Already Becoming Obsolete

Genetic testing may be even worse than flat screens when it comes to the speed at which they become out of date. Last fall, I took a genetic test for a recently identified genetic variation linked to a significantly increased risk of type 2 diabetes. With a family history of the disease and other risk factors, I was curious about my own genetic status. Fortunately, I didn't have that high-risk allele--but given my family history, I likely have other disease-linked variants.

At the Beyond Genome conference in San Francisco yesterday, I discovered that the test I took a year ago now screens for four genetic variants that boost risk for the disease. Those new additions are part of a flood of genome-wide association screens that have been reported over the past year. The rate may slow down as variants with the biggest impact on common diseases are identified.

The test I took was focused on a single disease, type 2 diabetes. Genome-wide screens, such as those offered by Navigenics, DeCode, and 23andMe, offer updates--either included in the initial fee or for an annual subscription--to their customers as additional information becomes available.

The issue led to an interesting panel discussion about who is responsible for tracking patients who do show an increased risk for disease. The problem is so new that there is no consensus yet. But Steve Murphy, founder of the personalized-medicine practice Helix Health, argued that it is the physician's job, just as it is his or her responsibility to make sure that patients with high cholesterol and other risk factors are properly monitored.

Here's an unrelated but fascinating fact that you may have heard before: a full 10 percent of fathers may not be the biological parent of their children, according to Charles Lee, director of cytogenetics at the Harvard Cancer Center. Lee's group didn't set out to examine these rates specifically--researchers do paternity testing as part of their standard genetic-testing process. In the process, they discovered that one in ten men are not the biological fathers of their children.