My mother died of ovarian cancer when she was 49. This was obviously a defining point in my life, I was 19. I turn 49 in a few years time and can’t help but feel like this age is my own personal, damoclean and literal deadline. I am a sceptic raised by scientists, I know that harbouring these thoughts are mostly an act of superstition, yet they still pervade. So I turned to science to help allay those fears, a couple of months ago I ordered a DNA test kit from 23andme.com.
Prior to November 2013 23andMe provided clients with nearly 200 reports connecting clients' genetics to various health conditions such as disease risk, inherited conditions, drug response and traits. They also provided ancestral information and an online community to connect with distant relatives if you so choose. In November, the FDA ordered that 23andMe stop revealing to customers their odds of contracting diseases in reports without clinical evidence to support such conclusions. The FDA was afraid that patients would take results as diagnoses, they felt some people should have counselling before getting their results. 23andMe continue to provide raw, uninterpreted data on your medical details (that you make get analysed with other services such as Promethease) and a full ancestral service.
There are a few things about the service that make me feel uncomfortable but I went ahead with it anyway. Why do I feel uncomfortable? Well, for starters 23andMe's CEO is Anne Wojcicki, the ex-wife of Sergey Brin who, when he help fund 23andMe, was running Google. I’m not a conspiracy theorist but it makes me feel cautious. 23AndMe promise privacy but my DNA will become part of a “Big Data” set that will be used by pharmaceutical researchers. In the best possible case scenario this Big Data will help cure or treat diseases that emanate from genetic mutations. In the worst case scenario my most personal data will be in the hands of a large corporation who wants to monetise it. New ways of using my data may develop that I can't even dream of yet. However they promise not to give my data to a third party without my consent. Then again they don't promise to get my permission before they sell the company.
Some of you may remember a book by Rebecca Skloot, published in 2010, called The Immortal Life of Henrietta Lacks (or even the earlier ,1998, one-hour BBC documentary The Way of All Flesh directed by Adam Curtis). It outlines the story of Henrietta Lacks, an African-American woman whose cells (taken without her knowledge in 1951 from her cancerous tumor) were cultured by George Otto Gey to create the first known human immortal cell line for medical research. This is now known as the HeLa cell line. She was a poor black tobacco farmer yet her cells became one of the most important tools in medicine, vital for developing the polio vaccine, cloning, gene mapping, in vitro fertilization, and more. Henrietta’s cells have been bought and sold by the billions, yet she remained virtually unknown until the publication of Skloot's book and her family couldn’t even afford health insurance. Stories like Henrietta Lacks', albeit 65 years old, are ones that companies like 23andMe (and clients like myself) need to bear in mind when dealing with such personal, biological data.
Prior to using 23andme, in March 2014, I was given the opportunity to have a free DNA test, via a cheek swab, by the Genographic Project. I find this project far less problematic in that it is run by a team of researchers who want to map human origins and migration paths and offer no health reports. They put part of their income from sales of DNA kits towards the Genographic Legacy Fund, which works to “conserve and revitalize indigenous cultures around the world”. I attended an evening put on by the Royal Society of New Zealand, listened to members of the team and some local participants talk about the project and the Africa to Aotearoa project, then had my DNA sample taken by a cheek swab. I got access to my analysed data online about 6 weeks later. I was curious to see how their data compares to the family history stories collected by my father, although of course the DNA will tell a much older story (50-60,000 years back) than the 500 years of family tree my father has traced. I was also curious to find out how much Neanderthal I have in me.
When I was conceived a single set of chromosomes in my father’s sperm and a single set in my mother’s egg combined to form my first single cell with a complete set of 23 pairs of chromosomes. These pairs determined which traits I inherited from each of them. Additionally, because only one chromosome from each pair of each of my parents are selected randomly I didn’t inherit all the traits of either of them, but a random selection and some are more dominant than others.
I share the same genes with you, but there are tiny variations within those genes - the result of mutations - called single nucleotide polymorphisms (SNPs) that make them uniquely our own. These SNPs are like typos that occur in replication allowing small variations into the sequence at particular locations on the genome, these have been compared to different cooks tweaking a recipe. There are around ten million of these SNPs in our DNA. These mutations can be insignificant, with little perceivable effect, but some mutations or combination of mutations can influence your appearance, response to certain drugs or food, or your susceptibility to a particular disease. However, no single genetic variant has a particularly large effect. Rather, there is a cumulative effect: innumerable tiny variants acting in aggregate, along with environmental factors, ultimately determine one’s height.
So then, what were the results? Well the results from each test I took differ slightly. Because the Genographic project is focused on prehistoric migrations their ethnic description of me was broader, they describe me as 40% Northern European (eg UK, Denmark, Germany), 39% Mediterranean (eg Sardinia, Italy, Greece, Egypt) and 19% South West Asian (eg India, Tajikstan, Iran). According to research and large data sets collected by the Genographic project my ancestors formed a group that came out of east africa 67,000 years ago and moved across the Sinai Peninsula. In present-day Egypt, members of this group lived in the eastern Mediterranean region and western Asia, where they likely coexisted for a time with other hominids such as Neanderthals (they calculate I am 2.1% Neanderthal and 1.5% Denisovan). After several thousand years in the Near East (about 55,000 years ago), individuals began to move out and explore the surrounding areas. Some moved south, migrating back into northern Africa. Others went west across Anatolia (present-day Turkey) and north across the Caucasus Mountains of Georgia and southern Russia. About 41,000 years ago some individuals moved across West Asia into Central Asia and then the Indus Valley. My ancestors remained in the Near East until about 28,000 years ago when they became part of a wave of migration into western Europe which marked the appearance and spread of what archaeologists call the Aurignacian culture, a culture distinguished by significant innovations in methods of manufacturing tools, standardization of tools, and use of a broader set of tool types, such as end-scrapers for preparing animal skins and tools for woodworking. Later migrations, such as those during the Neolithic Revolution and those triggered by the Bronze Age, brought additional groups containing different descendant branches of this line to Europe. I am haplogroup H, subgroup H27. Haplogroup H is 61% of the population of Ireland and 40% of the populations of Athens and Rome.
However this is ancient history, although it’s extremely interesting. I also wanted to know how closely my DNA matched my father’s genealogy research, that’s where 23andme comes in. But wait a minute, wasn’t I freaking out about my health? Six weeks after I filled a plastic tube with my spit I received an email telling me my results were ready. I downloaded my raw data and uploaded it to Promethease and ten minutes later I had a chart in front of me (which required a fair bit of interpretation). Some data was obvious (I’m a woman), some serious - I have increased risk of alcoholic liver disease and some forms of cancer. And some slightly silly - I’m more likely to think coriander tastes like soap (not true). It’s slightly mind blowing that from a tube of spit they can predict my eye colour and blood type. Some of it sounds like a horoscope, they tell me my personality is optimistic and empathetic, that I’m a worrier, with advantage in memory and attention tasks, more difficult to hypnotise, that I have increased susceptibility to novelty seeking. I think this sounds like me! They also say I have an increased chance of autism spectrum disorders (I'm not diagnosed but a family member is).
There are a few contradictory SNPs:
I have one SNP that says curly hair vs one that says straight (I have curly/wavy hair).
One that says freckles, vs one that doesn't (I have a couple)
Slow metabolizer vs normal metabolism (I claim a slow one as an excuse)
Slightly shorter lifespan vs better odds of living to 100 (hoping for the latter obviously)
I presume these may be a matter of either their individual dominance or dose-dependence whichever allows either to prevail.
There wasn't any really scary news, some cancers I have an increased risk for, however the normal risk for all these is so low that a slightly increased risk is still low. They recommend eating healthy, exercising and not smoking (funnily enough). All-in-all nothing to freak out about. On the upside I have a resistance to Prion Disease, which is transmitted by cannibalism, so I might be okay in the zombie apocalypse!
My ethnic mix according to 23andme, going back 500 years, is: 34.2% British/Irish, 17.4% French & German, .9% Scandinavian, 29.3% broadly northern european, 1.5% Italian, .6% Balkan, 8.3% broadly Southern European, .2% Ashkenazi Jew, 7% broadly European, .3% South Asian. Basically I’m a mongrel, this reflects the huge amount of movement around between the UK and the continent over the last 500 years. Oh and they tell me I’m 3% Neanderthal - that I’m in the 94th percentile!
The real surprise from 23andme, through their relative finder service, was the discovery of some 4-5th Greek cousins, relatives of my great grandfather who we know very little about, so I’m hoping to learn more about this part of my family tree. I also have distant cousins who are African American, we share a relative that many generations ago came from the UK to America. It’s a small world.