Startup offering DNA screening of 'hypothetical babies' raises fears over designer children
The Observer, 7 April 2014
Six years after Anne Morriss gave birth to a boy with a rare disease, she and a US scientist are giving would-be parents the chance to screen potential children for genetic conditions
Two days after Anne Morriss took her newborn son home from hospital, she received a bone-chilling phone call. The stranger on the end of the line asked her whether she was sure her baby was still alive. Rushing to the next room, she was relieved to find the baby was fine, but the call was from a Massachusetts state physician who told her that a routine scan had revealed her baby had been born with a rare and often fatal genetic condition.
The condition, MCAD deficiency, is caused by mutations in a gene involved in fat metabolism. Some babies born with a severe version of the disease do not live for more than fortnight because their bodies cannot derive energy from fat by normal methods when their sugar stores run out. An infant with MCADD (Medium-chain acyl-CoA dehydrogenase) can simply sleep beyond the amount of sugar in his or her body, without an efficient way of converting fat into energy to keep the brain alive, says Morriss.
"That first year was a blur of anxious, sleepless nights. I worried that he wasn't going to wake up in the morning. I worried when he was sick with a cold and didn't want to eat," Morriss recalls. But because the condition was picked up so early, Alec now has as good a chance as any child to live a long and healthy life.
That was six years ago. But for Morriss those early days were the start of something bigger. When she looked into it, she discovered that her son had inherited the condition as a result of a coincidence. MCADD affects 1 in 17,000 people in the US, but the sperm donor that she and her partner had chosen, using a sperm bank, had, unknowingly, been the carrier of this rare genetic mutation. And so had she.
Conditions like MCADD might be rare, but there are many of them and taken together they affect millions of people. Now Morriss has come up with a way to minimise the chances of other parents having to go through the agony that she experienced.
Along with her business partner Lee Silver, a scientist at Princeton University, she is about to launch a company called Genepeeks that uses the DNA of sperm donors and recipients to create "virtual babies". These in-silica offspring can then be screened for hundreds of genetic diseases, before ruling out donors who could pose a risk. In the future, the team hopes to make the technology available to any couple trying to conceive.
The new technology – which they call Matchright – could be a gamechanger in reproductive health technology, allowing prospective parents to make more detailed analyses of disease risk than ever before, without even needing a real pregnancy from which to extract DNA. But it will also allow them an unprecedented glimpse at what their future offspring might be like and could theoretically be used to screen for other qualities and traits besides diseases. Falling outside regulations normally used to deal with embryo testing and screening, the new technology raises important ethical questions about privacy, partner choice and the role that computing will come to play in reproduction. "We are entering a whole new era," says Ronald Green, a bioethicist at Dartmouth College in the US, "an era where biology becomes information."
Logging on to the web to look for donor sperm can be eerily similar to doing the weekly food shop. A couple of mouse clicks on the London Sperm Bank website, say, brings up donor 1015. He is mixed race, has blue eyes and dark hair, a BA in theology and is a Christian. The "more info" tab reveals him to be well travelled, worldly, with a gift for carpentry. Once you have made your selection, simply click "add to cart" and proceed to check out.
But while you can chose height, eye colour, religion, education, whether they have freckles and even which TV series they like, when it comes to a donor's medical information, there tends to be little to go on. Blood type is standard and many sites also provide a report in the form of a questionnaire about the medical history of the donor's family. How reliable these are is unclear, however – most of us would probably have scant details about the medical conditions of our own parents, let alone grandparents, cousins and so on. The amount of genetic testing of donors varies but the clinics tend to screen for a handful of conditions – cystic fibrosis, for instance. "The tests with the most breadth go up to about 100 [diseases]," Morriss says.
But part of the problem is that it is not all about the donor – it also has to do with the recipient's genome. There are hundreds of rare heritable diseases but the number of people affected is relatively small – only 4% of the population is born with genetic diseases caused by mutations in single genes (rather than being affected by a number of genes, such as breast cancer) and, because the number of people affected is small, there are far fewer treatments. One in three children with rare diseases will not make it to their fifth birthday.
Many of these conditions – including MCAD deficiency – are said to be recessive, which means that a person will be affected by it if they inherit two faulty copies of the gene, one from each parent. Those who have only one faulty copy will not have any manifestation of the condition and are unlikely to know they are a carrier – as was the case with Morriss. If two people who are carriers reproduce, they have a one in four chance of the child being born with that condition. "Recessive disease risk isn't likely to show up on a medical history," says Morriss. "No one in my family had ever had MCAD deficiency. I was a silent carrier for the disease, and we happened to choose a donor who was a silent carrier."
It was bad luck. But it made her wonder if anything could be done and she began to teach herself about genetics through books and articles. In the meantime, Lee Silver, a molecular biologist at Princeton, had been working for more than three decades in reproduction and development, first with mice, then with humans. With the explosion in the field of human genetics in the last decade, along with computer power and computational tools, and a faster, cheaper generation of gene sequencing technologies, Silver was beginning to apply the principles he had been studying in mice to humans. At the same time Morriss was digging into the genetics behind her son's condition, Silver was, in 2008, beginning to realise how his work "could be put together in a very useful way – [applied to] sperm banks and that we could predict the risk for particular diseases in the hypothetical offspring of two individuals".
When Morriss and Silver were introduced by a mutual friend in New York, they immediately discovered their common ground and came up with the idea of Genepeeks. While Silver is the science behind the company, Morriss provides the business side – and the layman's touch.
In her words, "the technology simulates the genetics of reproduction and we literally make digital sperm and eggs and put them together to make digital babies. We then look at the disease risk that's showing up in those future children."
The company then uses this to give clients their own personal catalogue of sperm donors – "the client comes in and we make a bunch of digital babies with every single donor in our network and then we filter out all the donor matches where there is an elevated risk of disease".