Each year at this time 23andMe puts together a list of the most interesting genetic findings of 2013. We’re doing that again but with a twist.
We want to include in our list a few things that aren’t findings or discoveries, but clearly, these stories have had a huge impact on the field of genetics. The fact that these stories made such a big splash beyond the world of science and health reporting illustrates how important genetics has become for everyone.
As far as research goes, in the last year, we’ve seen the continued rapid pace of discovery in genetic sciences. These new findings have included research into the biology of disease, mental illness and new insights into our understanding of human evolution. Researchers here at 23andMe are also a part of this push to understand not just the human story, but the biology of disease and the role genetics plays in our lives.
So let’s take a quick look back at the last year and 23andMe’s list of the Top Ten Genetic Stories of 2013.
THE ANGELINA EFFECT
Angelina Jolie’s revelation that she underwent a double prophylactic mastectomy after learning she had a mutation in the BRCA1 gene, brought genetic screening into sharp focus for everyone. In making her difficult choice, she took into consideration her family history – her mother died of ovarian cancer (also associated with BRCA1 gene mutation) and her aunt also had breast cancer – her ancestry and her age. Going public with her story also offered comfort to many women facing similar choices.
It probably wasn’t what Walt Whitman meant, but indeed we all “contain multitudes.” Our bodies are host to literally trillions of microorganisms that make up the “human microbiome,” and those organisms play a very important but not fully understood role in our health. There is also a link between the make-up of that microbiome and the genetic variation of our immune systems, which is another thing we haven’t yet fully figured out. But even without fully understanding how these all interrelate, doctors have started to use these important microorganisms to treat illnesses. Early in the year, the New England Journal of Medicine published a study that followed 16 patients who were treated for a severe gut infection with a fecal transplant. While it might be something you’d rather not talk about over dinner, the treatment of the Clostridium difficile infection worked in 15 of the 16 patients.
FIVE MENTAL ILLNESSES SHARE A COMMON GENETIC LINK
A study published in early 2013 found that five very distinct psychiatric disorders share an association with some variants in genes that control signaling in the brain. The large study looked at schizophrenia, bipolar disorder, autism, major depression and attention deficit hyperactivity disorder. Although these are very different conditions, the findings may help researchers better understand the underpinnings of these very different illnesses. Two of the four variants involve calcium channels, integral for signaling within the brain.
NOTHING TO SNEEZE AT
There’s an ongoing debate about the interplay between genetics and the environment in why there has been an apparent increase in the rate of allergies. There are many theories offered to explain this including the “hygiene hypothesis,” which suggests that an increasingly sanitized environment inhibits the development of the immune system. Another theory is that increased exposure to chemicals and pollutants are the culprits. The rate of allergies has more than doubled over the last decade. While this increase is pointing to environmental factors, genetics is an important component.
A study done by 23andMe scientists and researchers at the University of Bristol’s Avon Longitudinal Study of Parents and Children (ALSPAC) in the UK found new genetic associations for asthma and allergies. It was the largest genome-wide association study ever conducted on common allergies with data from more than 53,000 people. The study showed that there are also common genetic variants underlying allergies to cats, pollen and dust mites
HUMAN GENES CAN’T BE PATENTED
Not long after Angelina’s revelation, the Supreme Court unanimously decided to bar the patenting of human genes. The case involved Myriad Genetics, which has long held patents for breast and ovarian cancer screening. What’s not so clear from the Supreme Court’s decision is what sort of impact this decision will have on research and innovation. While several companies almost immediately jumped into BRCA testing, legal challenges by Myriad to stop those efforts quickly followed, leaving more doubt about how this will all play out.
THE WAY BACK
Scientists extracted DNA from a 400,000-year-old thigh bone found buried in a Spanish cave, known as Sima de Los Huesos, or Pit of Bones. Apart from the big deal of extracting genetic material from a really, really old bone – the oldest human DNA recovered yet – the find also gives us more information about human evolution, namely that it’s not as linear as some have thought. The DNA in the bone resembled that of ancient humans known as Denisovan.
Because of the time frame and the location, many had thought the bones would be from Neanderthals. The Denisovan DNA was a bit of a head-scratcher. Previous finds placed Denisovans in Siberia and only at about 80,000 years ago. Clearly, this adds more nuances to the story of human evolution. We can also add more pieces to that understanding after another DNA find this year. DNA from the 24,000-year-old skeletal remains of a boy buried near Lake Baikal in Siberia, has also altered researchers’ view of the migration patterns of early Europeans.
The DNA matched not just with Western Europeans but with Native Americans. This suggests that the earliest people to settle the Americas were a mix of both populations. While previous research has suggested that Native Americans descended from people who migrated from Siberia, this overlap with early Europeans is new. It also suggests that during the last Ice Age, people from Europe had migrated farther east than previously thought.
ALZHEIMER’S SEQUENCE DATA – CHAPTER ONE
The more information we can collect from people with the disease, the better we can understand them. Researchers working on Alzheimer’s disease got a huge boost in their efforts this year after the first batch of genetic data was made available as part of the Alzheimer’s Disease Sequencing Project. The project, conducted by the National Institutes of Health, makes available full genome sequence data on 410 people with Alzheimer’s. The hope is that by offering this information to a wide range of researchers, it will open up the possibility of new discoveries.
Hundreds of institutions worldwide are currently doing clinical and genetic research. If you could share that data and standardize how it is reported, you could make it that much more useful. That’s exactly what more than 70 medical, research and advocacy organizations did this year, the National Institutes of Health among them. They all agreed to set up a system to share genetic and clinical information. By creating a database of genetic variation and health information, it would offer researchers, and doctors, a powerful resource for discovery.
Illustrating the power of shared data, using data from the Electronic Medical Records Genomics Network (eMERGE) for short – researchers have identified dozens of new variants linked to diseases ranging from skin cancer to anemia. The eMERGE data set allowed researchers to search by gene variant to find associated conditions. As the database grows it will allow researchers to discover connections between seemingly unrelated diseases and genetic variants.
The power of big datasets that include not just genetic information but also phenotypic information, is part of what 23andMe is all about. This year 23andMe researchers leverage our database and certain phenotypes to functionally classify different genetic associations. our researchers presented some of our findings on this at the ASHG conference this year in Boston. Their findings show that on occasion, a single genetic variant will be associated with multiple different phenotypes. So for example, in autoimmune diseases, a single SNP influences multiple different diseases. Sometimes these shared associations are more surprising, such as the genetic association shared by both Parkinson’s disease and baldness. We’ve also found correlations between breast cancer and breast size, body mass index and food choice, and hair color and skin cancer.
MY, WHAT LONG TELOMERES YOU HAVE
Several papers this year indicate that genetic variants in telomere genes (such as TERT, TERC, POT1, etc.) not only influence the length of telomeres, which in turn is a good indicator of longevity, but those variants are also associated with certain cancers. Researchers in several different Genome-Wide Association Studies have found links to cancers such as multiple myeloma, breast and ovarian cancer, testicular cancer, lung cancer, and chronic lymphocytic leukemia.
23ANDME AND THE FDA
It’s not the kind of news we like, but there’s no way for us to do a roundup of the year’s big stories without mentioning that the FDA in December ordered 23andMe to stop offering new consumers access to their health-related genetic tests, while the company moves through the FDA’s regulatory review process. 23andMe remains committed to being a pioneer in the genetics revolution and has made its work with the FDA its top priority.
Making it all work will be good not just for the FDA and 23andMe, but for the future of the direct-to-consumer genetic testing industry. Individuals who want to understand their genetics will win too – that’s everyone’s goal. Here’s to 2014.