New Test Finds 580 Fatal Diseases Before Conception

PHOTO Craig Benson?s daughter was born with Batten Disease, a rare degenerative brain disorder that is fatal.
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Craig Benson thought his 5-year-old daughter just needed eye glasses when she complained about not being able to see the television set in 2008. But after consulting specialists, the family learned their beautiful daughter had a fatal neurodegenerative disorder -- Batton disease.

"In an instant, a word we had never heard of changed everything," said Benson, 48, and CEO of an Austin, Texas, biotech company. He and his wife Charlotte never knew they were carriers of the rare disease.

Christiane, now 8 and legally blind, faces a grim prognosis: seizures, memory loss and finally death by her late teens or early 20s. She is one of about 700 other Batton cases in the country.

Rare diseases account for 20 percent of all pediatric mortalities in the United States, according to the Beyond Batton Disease Foundation, the nonprofit Benson founded after his daughter's diagnosis.

But now, largely because of Benson's passion, a new DNA test has been developed to detect parents who are carriers of 580 of the most severe inherited childhood diseases -- not only Batton, but muscular dystrophy, immune deficiencies like the "Bubble Boy" syndrome and Pompe disease, described in the 2010 film, "Extraordinary Measures."

The test, which was announced in the journal Science in Translational Medicine, uses genetic sequencing to identify recessive mutations before a couple decides to become parents.

See all the recessive diseases here.

The average person carries at least two to three gene mutations that can cause disease. When both have the same mutation, the chance of having an affected child is 1 in 4; the risk of having a child who is a carrier is 2 in 4; and the odds of having a normal child is 1 in 4.

The carrier screening test is cheap -- less than $400 for hundreds of conditions -- and could be marketed in the near future, according to Dr. Stephen Kingsmore, now a physician-researcher at Children's Mercy Hospital in Kansas City, Mo., where clinical work will be done.

"The long-term impact could be phenomenal," said Kingsmore, who headed up the research at the National Center for Genome Resources in Santa Fe, N.M.

The test will be sold through Benson's foundation to eventually find cures -- a kind of "venture charity," he said.

Right now, preconception testing is recommended for just a few diseases -- like Tay-Sachs and cystic fibrosis -- and can cost as much as $2,000 each.

If the Bensons had access to this test, they might have decided to adopt, turn to in vitro fertilization and test the embryos before implantation or seek egg and sperm donors.

Their 6-year-old son Garland, who was conceived before Christiane was diagnosed, is healthy and not a carrier.

The test will likely be a blood test and later a simple swab of the cheek. Egg and sperm banks may be the first industry to adopt the testing to screen potential donors.

Genetic Testing Can Help Treatments

The test is a boon, even for those who are carriers and decide to take the risk and get pregnant so treatment can begin sooner.

"Some will go ahead and plan a family," said Kingsmore. "But let us prepare for the potential they may have a sick child and get them into a network of support or at least make those introductions when the baby is born so they don't feel hopeless and helpless or lost in the world."

Elizabeth Joshi of Evansville, Ill., could have been helped by this test, as she spent months trying to get a diagnosis for her son with Joubert syndrome, a rare genetic disorder that affects the brain's cerebellum.

Though it can vary in severity, it causes breathing problems, seizures and often fatal kidney disease. Only about 650 families in the U.S. are affected.

"Not knowing what was wrong with him hit me like a ton of bricks," said Joshi, 40, and a former lawyer.

Shaan, now 6, is unable to eat solid foods and cannot speak or walk. How long he will live is "a big question mark," according to his mother.

"He seems very aware of what's going on," said Joshi. "But it's so hard on him physically for him to express what he needs and wants and leads to a lot of aggravation for him. It's a daily struggle."

Shaan's 8-year-old sister in unaffected, but Joshi has decided not to have any more children.

"We are personally not willing to roll that dice," she said, "knowing what he deals with."

Shaan Joshi, 6 and shown here with his sister, Shefali, has Joubert syndrome and cannot walk or speak.

Scientists look to the 40-year history of a carrier blood test to detect Tay-Sachs, a childhood disease that has been virtually eliminated among people with Eastern European Jewish ancestry.

Public education campaigns in synagogues encouraged all parents to be tested before conception. Now, mostly non-Jews, though their risk is not as great, are among the 100 American children who have the disease, according to the National Tay-Sachs and Allied Diseases Association (NTSAD).

Tay-Sachs, a neurological disorder, is fatal in children. They are missing a critical enzyme, which affects their swallowing and disrupts normal development. Many go on to have feeding tubes and most die between 2 and 8 years old.

Tay-Sachs Devastates Affected Families

Deborah Spielman, a 51-year-old construction manager from Newton, Mass., never bothered to do the Tay-Sachs testing until she was pregnant with their first child.

The results got lost in the mail and were deemed, "inconclusive." But when she was just shy of six months pregnant, positive results were confirmed and she aborted.

"I was the type of person who would have said before I knew anything about Tay-Sachs, I wouldn't abort," she said. "I wouldn't abort if I had a child with Down syndrome. I could have dealt with that. But I learned how devastating Tay-Sachs was."

She aborted another positive pregnancy early on, but has since had three healthy children, now 21, 18 and 5.

Deb Spielman of Newton, Mass., had seven pregnancies, two of which were affected by Tay-Sachs syndrome. She eventually had three healthy children, Maddie, now 21; Jacob, 18; and Maya, 5.

Now, her brother is getting married and has asked her if he should be tested. "What happens if they are both carriers?" asked Spielman. "Is that going to change the way you guys feel about each other? It could be a cloud over the wedding."

Tim Lord of New York City lost his 3-year-old son Hayden to Tay-Sachs in 2000. His brother, an identical twin, also lost a child to the disease six months later. The twins were not Jewish so they never sought testing.

"We didn't even know to be tested," said Lord, who now has two healthy girls.

Although the new genetic test will not replace the standard enzyme test for Tay-Sachs, Lord said it should be "taken seriously as part of an educational and advocacy process."

"It only makes sense to move forward thoughtfully and carefully," he said. "But it absolutely is a very positive thing for a young family."

"I never would have traded in my son," he said. "But I would never knowingly bring a child into the world who suffered the way he did. It's dreadful. It's not something like Down syndrome where you can bring a child in and build a life, just a different life. This was brutal."

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