This Christmas it’s likely that more people than ever before will spit into a tube, or swab some cheek cells and send the result off for DNA analysis. Millions in the US have already done it, and the craze is spreading. But what happens when you find out a lot more than you were expecting?
Three years ago, Jenny decided to take a DNA test “just for fun”. The youngest of five children, she had always been intrigued by stories about her ancestors. As a teenager she loved looking at old photographs with her grandfather and over the decades she had painstakingly pieced together her family tree.
Once her children were grown and she had more time on her hands, Jenny, a freelance writer from Connecticut, began going to genealogical conferences and workshops to improve on her methodology. “Everyone was talking about doing these DNA tests but I wasn’t keen – it all sounded very scientific and I have no head for that.”
Yet Jenny was curious to see what the test might reveal about her ethnic background, so she sent off for a kit and gave it a go.
There were no surprises when the results revealed her heritage as largely British, including Scottish, with a smattering of genes from Scandinavia. “Nothing exotic,” she laughs.
But a year later she did a test with another genetic testing company and persuaded her brother to do one too. This time there was a surprise. The email with the results included a chart that she struggled to understand – but something written underneath immediately caught her eye: “Estimated relationship: half-sibling.”
Jenny assumed her brother had done something wrong when he took the test. She decided that he must have left the kit lying in the sun or forgotten that you are not supposed to eat or drink an hour before providing the saliva sample.
“I was mad at him,” says Jenny. “I thought – how typical! I asked him to do one little thing and he still couldn’t get it right. I tried to rationalise it but at the same time there was this pit in my stomach.”
Jenny searched for answers online and learned about the centimorgan – a unit of genetic linkage. Siblings typically have 2,500 centimorgans or more in common but Jenny only shared 1,700 with her brother.
Tormented by doubt, she asked her father’s cousin, a woman in her 90s, to take the test too. “She had helped me a lot with genealogy, we had traded photographs and she was a very sweet person,” says Jenny. “I feel terrible that I didn’t tell her the real reason. I said it would be a fun thing to do and promised I’d send her the report.”
Six weeks later Jenny was sitting in bed with her iPad when the results popped into her inbox. Unlike her brother, she shared no DNA with her father’s first cousin.
“I could just feel my heart breaking,” says Jenny, her eyes filling with tears. “I thought, ‘Oh, my god it’s true!’ My poor husband sleeping next to me had no idea what was going on. I have never felt so alone.”
- Family history has been described as the second biggest hobby in the US after gardening, and as the second biggest activity on the internet after pornography
- The price of DNA testing kits has plummeted – in the US they’re available for less than $100, while one UK high street chain sells them for £80