A newly developed test could screen would-be parents for hundreds of different disease genes, to make sure they are not passed on to any future children.
The test's makers say it
should cost less than $400 and that routinely offering it to prospective
parents could someday eliminate many deadly childhood diseases.
definitely want it to be pre-pregnancy. We do want it to be couples,"
says Stephen Kingsmore, a physician-researcher at Children's Mercy
Hospital in Kansas City, Mo., who led the team that developed this new
test. "I think it's going to be a personal decision, whether a couple
wants to be tested."
The inspiration for this new test came from Craig and Charlotte
Benson, of Austin, Texas. In 2008, their daughter Christiane was
diagnosed with Batten disease, a rare neurodegenerative disorder that
currently has no cure. It progresses from vision loss to memory problems
and seizures, and eventually death.
her mom and I carry a gene mutation, a single gene mutation," explains
Craig Benson. He and his wife didn't know they were carriers before they
had children — indeed, they'd never heard of Batten disease.
Benson works for a biotech company, so soon after his daughter was
diagnosed, he and his colleagues were discussing how difficult it is for
rare childhood diseases to get much attention or research that could
lead to cures. They wondered about new ways of trying to prevent these
They knew that one devastating
childhood disease, Tay-Sachs, has been virtually eliminated in people
with Eastern European Jewish ancestry. This has been done by offering
screening tests to would-be parents with that background. If both
parents carry the Tay-Sachs mutation, they can take steps so that they
won't have a baby with this disease.
thought, you know, that's a great idea and a great strategy. Why is that
not more broadly applied?" says Benson, who noted that DNA testing
technology has been advancing rapidly.
his colleagues approached Kingsmore, who was then at a nonprofit called
the National Center for Genome Resources in Santa Fe, N.M. They asked
him if it would be possible to make an affordable test that could screen
all prospective parents for numerous rare genetic diseases.
This week, in the journal Science Translational Medicine,
Kingsmore's team describes that test. For less than $400, it can check a
person's DNA for all mutations in genes related to nearly 448 severe
And Kingsmore says that's just the beginning.
the next six months we'll be taking the number up to 580 conditions,"
he says, "at which point we'll have represented just about every
childhood disease that's severe enough to merit inclusion."
average we found that each of us carries two or three mutations that
could cause one of these severe childhood diseases," Kingsmore says.
Right now, preconception
genetic screening is recommended for just a few diseases — like
Tay-Sachs and cystic fibrosis — in certain populations that have a
a couple of companies offer a routine preconception screening test for
couples. For example, one test, sold by a company called Counsyl in
Redwood City, Calif., is offered through doctors and IVF clinics. But
Kingsmore says these currently available tests screen for far fewer
diseases and can detect only known mutations — and he says for many rare
disorders, all the mutations are not known.
new test could become widely available soon, and Benson wants to offer
it through a nonprofit he started, the Beyond Batten Disease Foundation,
so that doctors could provide screening to everyone who wants it.