23andMe Genomic Research
The idea sounds like something out of a science fiction novel: spit in a little vial, send it through the mail, and not long after, receive a detailed report assessing your risk for dozens of diseases, traits and conditions. This seemingly futuristic “personal genome test,” however, is exactly what has been brought to the market by the Silicon Valley-based biotechnology company 23andMe.
23andMe, named for the 23 pairs of chromosomes making up the human genome, gained popular attention when it began offering its low-cost personal genome service in 2007. Customers send in their saliva using a special kit, from which the company extracts their DNA. They then sequence the DNA, paying special attention to areas of the genome known to cause conditions like breast cancer or diabetes. Once the analysis is complete, customers can view their results online. There they can discover everything from fun personal quirks (such as whether they’re likely to sneeze upon looking at a bright light) to more serious health risks (such as increased disposition to Alzheimer’s disease or hypertension).
In November 2013, however, the U.S. Food and Drug Administration (FDA) ordered 23andMe to “immediately discontinue marketing” its personal genome service, claiming that it is a medical device requiring prior federal approval. The FDA is mainly concerned with the “potential health consequences that could result from false positive or false negative assessments.” They point out that risk estimates are often inconsistent from one test to another, and that genetic results may drive customers to take extreme or dangerous actions, such as unwarranted surgery or chemotherapy to prevent cancer. Proponents of 23andMe, however, point towards studies showing that people who receive genetic tests do not experience changes in anxiety levels, and may even improve their eating and exercise habits (perhaps in response to a high risk factor for cardiovascular disease). As of this writing, 23andMe is no longer offering its health-related genetic reports, but still provides ancestry analysis.
The importance of 23andMe, however, reaches beyond individual genetic tests. “One of our main goals is to dramatically accelerate the pace of research,” says 23andMe cofounder and CEO Anne Wojcicki.
Scientists are particularly interested in areas of the genome containing what are known as single nucleotide polymorphisms. These SNPs (pronounced “snips”) are changes in a single letter (base pair) of a DNA sequence. They serve as the basis of a large number of heritable traits, and are responsible for predisposing people to certain diseases. For example, women with mutations in the BRCA1 gene have a significantly increased risk of developing breast cancer — in some instances, as high as an 80% chance by age 90.
By comparing the DNA sequences of diseased and healthy individuals, scientists can often pinpoint locations in the genome responsible for causing a particular illness. For example, if one hundred people with disease X all have a certain mutation, while one hundred healthy individuals do not, then that mutation is very likely associated with the development of disease X. This method, known as a genomewide association study (GWAS), has been successfully used to identify the genetic basis of many complex diseases. Knowing the risks and causes of diseases will be essential in proper medical treatment.
Here is where companies like 23andMe come into play. To perform a GWAS, scientists need a lot of raw genomic data from a large number of people. Recruiting new volunteers for each study is both costly and time-consuming. With 23andMe’s immense database, however, researchers gain immediate access to the genomic data of over 650,000 individuals. “Instead of actually having to do clinical trials the old-fashioned way, we could enable researchers to get their answers instantaneously,” says Wojcicki.
With 23andMe’s immense database ... researchers gain immediate access to the genomic data of over 650,000 individuals.
In January 2015, 23andMe announced that it would be sharing its genomic database in a deal with pharmaceutical giant Pfizer. Using this data, Pfizer intends to find new targets to design drugs and treat diseases like irritable bowel disease and lupus. Wojcicki plans to make similar deals with more pharmaceutical and biotechnology companies throughout the year.
The emergence of personal genome services like 23andMe reflects a broader trend in the practice of medicine, which has been called the genomic revolution. “We are witnessing an avalanche of exciting results from these kinds of studies as they uncover subtle and previously unsuspected genetic factors contributing to health and disease,” says Dr. Francis Collins, director of the National Institutes of Health. “Research groups who have been doing the tough clinical work of recruiting and examining large numbers of people at risk for these diseases can now use genomic technologies to shine a bright light on the entire genomic landscape of their patients. The findings will enhance how we predict, diagnose and ultimately design personalized prevention and treatments for our patients.”