Family Matters

Test Your DNA for Diseases — No Doctor Required

Anne Wojcicki plans to sell whole-genome sequencing directly to consumers, no doctors needed

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Spencer Lowell for TIME

Anne Wojcicki, co-founder of 23andMe, based in Mountain View, Calif., is planning to make whole-genome sequencing available directly to the public

When Anne Wojcicki’s son was a baby, she ran a swab across the inside of his cheek, collecting DNA to send to a lab. Last year, when she was pregnant with her daughter, she tested her amniotic cells. The goal in each case: to get a glimpse of her children’s genes and determine whether they contain certain kinks that increase the risk of developing anything from gallstones to multiple sclerosis. “As a parent,” says Wojcicki, “the most responsible thing I can do is get as much information about my children as possible so I can then think through how I can make them as healthy as possible.”

Wojcicki isn’t just any random parent, though. She’s a Yale-educated biologist and the co-founder and CEO of 23andMe, a company in Mountain View, Calif., that sells DNA analysis directly to consumers — no doctor required (See TIME’s inside look into 23andMe’s genetic testing lab here). “Your information is your information,” says Wojcicki, who is married to Google co-founder Sergey Brin. “If you want it, you should be able to have it.”

The second in a five-part series exploring the promise and pitfalls of sequencing children’s genomes

Genetic tests have been around for years, but in 2003 scientists took the field a step further, announcing the first complete mapping of a human genome — an entire genetic code. Sequencing, or “reading,” a person’s genome is one of the newest, most controversial tools in the medical arsenal because of the mother lode of information it contains about future disease risk. Genetic markers for heart disease or cancer may spur consumers toward healthier behavior. But when it comes to conditions such as Alzheimer’s and Parkinson’s that can’t be prevented, many experts are divided on whether knowing is helpful or harmful.

Yet even as physicians and bioethicists wrestle with the implications of revealing dark DNA secrets, entrepreneurs like Wojcicki are planning to make whole-genome sequencing (WGS) available directly to the public. Other companies, like San Diego–based Illumina, are already offering the test to what its CEO, Jay Flatley, calls a “healthy and proactive” demographic.

So far, these tests have been aimed mainly at early adopters: tech-savvy folks who buy the latest smart phones and are comfortable with life on the cutting edge. But as prices keep falling, the audience is likely to expand. Can the average mom or dad handle knowing all about the risks lurking in their kids’ DNA?

“Everyone at this point is flying by the seat of their pants,” says Jim Evans, a medical geneticist at the University of North Carolina at Chapel Hill who is editor-in-chief of Genetics in Medicine. “The technology is outpacing us.”

Parents, of course, are often particularly receptive to the latest promises of medical science. Firms offering private cord-blood banking bombard expectant moms and dads with what-if scenarios that can tempt all but the most hard-bitten parents-to-be to spend thousands of dollars storing frozen cord blood that will most likely never be used.

(MORE: Will My Son Develop Cancer? The Promise (and Pitfalls) of Sequencing Children’s Genomes)

image: 23andMe's custom genotyping array chips are mounted for processing. Each chip probes individual samples for approximately one million genetic variants (or single-nucleotide polymorphisms - SNPs).

23andMe’s custom genotyping array chips are mounted for processing. Each chip probes individual samples for approximately 1 million genetic variants (single-nucleotide polymorphisms, or SNPs). Photograph by Spencer Lowell for TIME

Adding to the confusion: it isn’t easy to interpret sequencing results. Much of our genome remains a mystery, and sifting through the sheer quantity of information generated by sequencing can be overwhelming. Even medical professionals, after years of training, are often unsure what to make of the pages and pages of data that genomic sequencing spits out. Dr. David Margulies, who oversees a Children’s Hospital Boston initiative to make genetic and genomic insights more accessible, says better interpretation is “the last major barrier to widespread clinical use of DNA sequencing.”

In Cambridge, Mass., a company called Knome is working on erasing that barrier. For $2,000 per person, Knome does the data crunching needed to interpret a sequence, figuring out what all those billions of nucleotides, or DNA “letters,” mean. When the company launched five years ago, its clients were mostly universities and pharmaceutical companies. Now it’s going mainstream. “There has been a big shift this year,” says Knome CEO Martin Tolar. “We have been swamped with requests from clinics.”

(SPECIAL: A Look Inside 23andMe’s Genetic Testing Lab)

Knome’s software separates the data into tiers of relevance. Says Tolar: “There will be a report about different levels of importance that says, These variants are actionable, meaning you know what they are and can do something about them, these variants don’t seem relevant, and these are novel variants we haven’t seen before and don’t yet understand.”

Yet even though some companies are making complex genetic data more digestible, direct-to-consumer tests like the ones 23andMe offers have been criticized for their methodology, which some critics regard as genetics-lite. To weigh in on a person’s predisposition for conditions including celiac disease and melanoma, 23andMe looks only at a small fraction of points along someone’s genome. The company is currently seeking FDA approval for this approach. In the past year, other direct-to-consumer DNA companies have closed up shop before undergoing this kind of regulatory scrutiny.

(MORE: Genetic Testing for Kids: A Good Idea?)

image: One of the sample processing rooms in the CLIA-certified laboratory; DNA samples are applied to 23andMe's custom genotyping array and analyzed here.

One of the sample-processing rooms in the CLIA-certified laboratory, where DNA samples are applied to 23andMe’s custom genotyping array and analyzed. Photograph by Spencer Lowell for TIME

Eventually 23andMe intends to start offering WGS, which dives much deeper by analyzing all 3 billion base pairs, or sets of letters, that make up a person’s DNA alphabet. But unlike the dozen or so academic labs and private companies that are already sequencing genomes or exomes (the subset of genes that codes for proteins, which regulate the body’s tissues and organs), 23andMe would not require a physician’s approval for this process. That means that one day, accessing a sophisticated sequencing test could be as easy as buying a pregnancy test at a drugstore.

Many in the industry remain skeptical about cutting out the clinician. GeneDx, a Maryland-based genetic-testing company, charges $5,000 to sequence an individual’s exome. But the company will run its tests only per a doctor’s request. “If you leave out the physician, there could be significant misunderstandings,” says Amar Kamath, GeneDx’s vice president of marketing.

Parents, for example, may not know that genes are far from the last word in determining disease risk; environment plays a significant role too. And they may be unprepared to respond to the news that their children are predisposed to develop serious diseases as adults. It can be an emotional blow — and a lifelong burden — if a mom learns that her baby girl carries a mutation that increases her risk of breast cancer or a dad finds out that his aspiring linebacker is genetically predisposed to developing Alzheimer’s. That’s why Illumina’s Flatley personally vets every clinical case and refuses to sequence kids who aren’t sick. “We don’t do this just for fun,” he says. “We do it on children when we’re trying to save their lives. We don’t believe parents have a legal or ethical right to do this.”

Wojcicki doesn’t share that viewpoint personally or professionally. Since 23andMe launched in 2006, more than 180,000 people have been tested as the price has fallen from $999 for information on 14 traits and health risks to $299 for more than 200. About 3% have been children, and Wojcicki thinks demand for testing kids is on the rise. “I do believe at some point in time everyone will be genotyped at birth,” she says.

(MORE: Scientists Decode an Unborn Baby’s DNA. Is It Cause for Celebration — or Alarm?)

Nor does she disagree about the value of having a doctor weigh in; she says she had the data from her unborn daughter’s testing sent to her pediatrician. “I did actually find it helpful to walk through that with her,” says Wojcicki. But she takes issue with the need for a physician to sanction the tests in the first place.

Though Wojcicki won’t discuss her kids’ results, she recently mused on her company’s blog about her motivation for testing her children. She’s particularly interested in Parkinson’s disease because her husband has a genetic mutation that heightens the risk by up to 80%. Brin’s mother has the disease; his kids stand a 50% chance of inheriting it.

Wojcicki, who is 39, notes that some genetic findings could be used to influence parents’ everyday decisions, all the way down to which sports their kids play. For instance, there’s a gene mutation called APOE-4 that indicates a higher risk of developing Alzheimer’s. In people who test positive for APOE-4, research has associated traumatic brain injuries with a greater likelihood of brain disease.

In other words, if you know your kid has the APOE-4 gene mutation, you just might knock youth football or ice hockey — Wojcicki played on the varsity team at Yale — off the list of extracurriculars. At the least, you’d probably give extra consideration to insisting that your child wear a helmet on the soccer field.

For Wojcicki, this emphasis on genetic testing has nothing to do with overprotective parenting and everything to do with preventive medicine. “The way I can potentially start to prevent certain illnesses is to know what they’re at higher risk for,” Wojcicki recently told TIME. Her grandmother had macular degeneration; when testing revealed that some of Wojcicki’s nieces and nephews are at higher risk of it, she responded by buying them high-quality sunglasses. If her own kids were predisposed to developing diabetes, she’d encourage healthier eating. “I want to do everything I can to potentially enable my children to be disease-free,” she says.

This is the second in a five-part series exploring the promise and pitfalls of sequencing children’s genomes. Read the full series.

MORE: Complete Genetics Coverage