Eric Topol just found out he carries the recessive alleles for two serious genetic diseases: A metabolic muscle disease called myoadenylate deaminase deficiency, and hereditary hemochromatosis – a condition that causes excessive iron absorption in the body.
The lauded Scripps cardiologist used this knowledge as a platform to promote carrier screening via Twitter. After all, carrier screening is a powerful tool to head off serious medical conditions – testing couples getting ready to have children to learn whether they carry the genes that cause diseases like cystic fibrosis, Tay Sachs and many others.
“It’s the ultimate form of prevention that we don’t use – but we need to at least start thinking about it,” Topol said in a phone interview with MedCity News.
Topol had his genome sequenced at Illumina, and two weeks ago it was freshly annotated to reveal all insertions and deletions – which is how he stumbled on the knowledge that he very well could have passed on serious disease to his children.
“My wife wasn’t a carrier for these diseases, thank goodness,” Topol said.
Topol cited a recent Tablet Magazine article, “Tinder for Tay-Sachs,” in which prospective mates are informed – even before the first date – on whether they’re carriers for this debilitating neurological disease. The service is meant for Jewish couples that carry an allele that’s highly prevalent among the Ashkenazi population.
“That may be extreme, but the whole idea is that at least you should know,” Topol said.
That way, if parents who are both carriers choose to go ahead and have a child, they’re armed with the knowledge of what to look out for. Or, with that knowledge, parents-to-be can explore alternate options in having a child – like using an egg or sperm donor.
But won’t carrier screening enable that overwrought Gattaca idea of the future of genomics?
“I find that ridiculous, frankly,” Topol said. “We’re not talking about designer babies, but about preventing serious illness.”
We have the knowledge, after all, to prevent a whole laundry list of serious genetic diseases. He’s actually written fairly extensively on the subject, particularly in his highly cited 2014 paper in Cell: “Individualized Medicine from Prewomb to Tomb.”
“With a little work, we could prevent what could be a really tragic story,” Topol said.
So how do we bring carrier screening to the mainstream? It’s about lowering costs and increasing awareness, Topol said. The Angelina Jolie effect has brought a lot of awareness to genetic testing.
“We need some people with that large public profile to stand up for carrier screening,” Topol said. “The other thing: It needs to be really inexpensive.”
Right now, the carrier screening cost hovers around $349 for Bay Area startup Counsyl; Topol says such tests need to be well below the $100 mark to go mainstream.
Competition will drive a lowering of costs, he says – up against Counsyl is San Diego startup Recombine, for instance, that aims to accomplish the same broadscale acceptance of carrier screening.
“The pre-womb story has to get democratized, it has to be really inexpensive, and really alluring for couples,” Topol said.