New Down Syndrome Test Hailed as Promising

Unlike Republican VP nominee Sarah Palin, an estimated 87 percent of all women carrying a child with Down syndrome don't learn the news until delivery.

"I was grateful to have all those months to prepare," Palin, who underwent amniocentesis five months before the birth of her son, Trig, told People magazine. "I can't imagine the moms that are surprised at the end. I think they have it a lot harder."

One in every 733 babies -- or around 5,500 each year -- is born with Down syndrome, the most common genetic condition in the United States, causing an array of physical and mental challenges for both child and parents.

Until now, prenatal genetic testing for Down syndrome has either been too late, too invasive or inaccurate, giving women little choice in whether to carry or terminate the pregnancy.

But now, one company is investigating the possibility of a new non-invasive blood test, administered as early as 12 to 13 weeks into the first trimester, that detects genes that are behaving in a way that is linked to Down syndrome.

In an experiment earlier this year, the test has already been used to screen the fetuses of 200 pregnant women, with no false negatives. Further testing involving more women is scheduled for this month.

Despite early promise, the testing is still in its early phases. Dr. Lee Shulman, head of the Section of Reproductive Genetics at Northwestern University's Center for Genetic Medicine, has investigated fetal DNA testing since the late 1980s. He said that it remains anyone's guess as to whether the test will eventually become a viable early screening or diagnostic offering for curious expectant moms.

"The medical community knows very little about this," Shulman said. "I am somewhat concerned about this company going with investors and marketers rather than waiting for robust and significant clinical trials... Why are they talking about marketing when they don't have anything that has been put to the test?"

Still, Shulman said the idea of such a screening -- which if proven to work, could offer what he said would be the first ever first-trimester direct genetic testing for the condition -- is "fascinating."

Population With Down Syndrome Could Drop

But advocacy groups warn that the test -- which gives women the option to end a pregnancy sooner -- could diminish an already small population of about 400,000 that has Down syndrome.

About 90 percent of women who learn they are carrying a child with Down syndrome choose to end their pregnancies, and easier testing could increase those numbers, stymying support and fundraising for the disorder.

And some say the expanded technology raises ethical questions

"It's 'Gattaca World,'" said Los Angeles filmmaker Will Drinker, referring to the 1997 movie about a society that analyzes its citizens' DNA to determine where they belong.

"It's a dead race, but there'll be a whole new race of perfect people that have blue eyes and blond hair and are what their parents want," said Drinker, whose 23-year-old brother has Down syndrome. "I am afraid of the opposite of Dan."

The prenatal test, called SEQureDX , is being developed by the San Diego-based company Sequenom, which will conduct further studies this fall and hopes to market the product in early 2009.

Prenatal Genetic Testing

Sequenom's stock jumped 78 percent in June when the new product was announced. And even though doctors said the test faces more hurdles, its "approach" could revolutionize the way doctors diagnose other chromosomal abnormalities.

"This is an innovative company, and the technology that is under development shows huge promise," said Dr. Laird Jackson, professor of obstetrics and gynecology in genetics at Drexel College of Medicine in Philadelphia. "They have the basis for a test, but it isn't clear how applicable it is."

Shulman agreed. "Ultimately, for this to be widely used and seen as medically appropriate, it would need the support of professional organizations like the American College of Obstetricians and Gynecologists [and other bodies]," he said. "Without rigorous and robust testing, none of these professional organizations are going to jump on board."

But the approach is a novel one. Down syndrome most often occurs when a child has three copies of chromosome 21. Unlike previous blood tests that measure protein markers in the mother and only predict the likelihood of Down syndrome in the fetus, this test looks at the fetus's genes. In the first small trial on humans, the test showed no false positives.

Safer for Mother and Fetus

And if it turns out that the test is a reliable one, Sequenom executives said, it could be a boon for expectant mothers.

"It's a better mouse trap," said CEO Harry Stylli. "I don't want to trivialize this, but it is a superior mouse trap, safer for the mother -- a simple blood draw -- and safer for the fetus."

For decades, amniocentesis has been the gold standard of prenatal testing, performed on 430,000 to 600,000 women a year. The procedure is usually performed at 18 weeks gestation when termination can be traumatic. Doctors insert a needle into the uterus and withdraw amniotic fluid, which can cause fetal injury or miscarriage in one out of 200 patients.

Chorionic villus sampling -- testing the placental tissue -- is also invasive, and can be done at as early as 10 weeks, but it carries a one in 100 risk of miscarriage.

Newer, noninvasive blood serum tests can be done earlier, but yield a 5 percent false positive rate. Each year about 40,000 of the 3 million who take the blood test are directed toward amniocentesis for follow-up.

"That's a dilemma for women," said Stylli, who said SEQureDX will soon complement and perhaps one day replace amniocentesis. It can be offered at as early as 12 to 13 weeks.

Pregnancy and Down Syndrome

The National Down Syndrome Society has said in a prepared release that although the new test "may provide improved safety and more accurate results," explaining those results can be problematic.

According to a survey that was cited in the medical journal Pediatrics, nearly 25% of doctors admit to giving patients negative information or actively urge parents to terminate their pregnancies.

Dr. Brian Skotko, a senior resident at Children's Hospital in Boston who has a 28-year-old sister with Down syndrome, conducted a survey that revealed, "The majority of mothers said that doctors were incomplete, inaccurate, or offensive when it came to delivering a diagnosis of Down syndrome."

He said that according to some research, an estimated 90 percent of mothers who chose to terminate a pregnancy because of Down syndrome considered the condition "too severe, that they would be sad all the time and would be a burden to the family."

"All [mothers] described moments of shock, grief and sadness," he told ABCNews.com. "The majority expressed disappointment in the way that their physicians delivered the news."

But, he said, nearly all those families eventually "learn the joys of having such a child."

In his case, his sister taught him many of life's lessons. "When others mock, she teaches me to stand up and defend myself," he said. "I see how hard she works, and it makes me more determined to work."

Children With Down Lead Joyful Lives

Skotko said parents need to know that their children can lead "full and productive lives." His sister now lives in Ohio and works two jobs and has a boyfriend.

Still, there are challenges. About half of the children born with Down syndrome have cardiac deformities, but most of those can now be repaired. With medical advances, they can expect to live until well into their 50s or 60s.

Studies also show that siblings of children with Down syndrome are more empathetic and caregiving than others.

Will Drinker, 22, is chronicling his older brother Dan's life on video: his first date, dealing with death and even his YouTube endorsement of Barack Obama. Together they have created the Web site dandrinker.com.

Despite Down syndrome, Dan Drinker holds down two jobs -- as a bagger at Acme and working at a center that provides services for those with developmental disabilities.

Dan's worth is unquestioned in the Drinker family. To date he has saved two lives: a younger sister who nearly drowned in a pool and a suicide jumper who fell into the water near Dan's boat.

"One of the elements of the project is attempting to save Dan," Drinker told ABCNews.com. "This is a historic document. This thing we know as Down syndrome will probably be a bygone era."

Ethics of Ending Pregnancy

Doctors like Skotko agree that when it comes to ending a pregnancy, doctors must "respect the wishes of patients," but say that many at home are misinformed.

He said an estimated 80 percent to 90 percent of all mothers believed caring for a Down syndrome child would be "too severe, that they would be sad all the time and would be a burden to the family."

That was the case with Deirdre Featherstone, a New York City jeweler, who had scheduled amniocentesis when she became pregnant at the age of 37 but then canceled it.

"One of my theories is that certain things are meant to be," Featherstone told ABCNews.com.

But she still worried. "Having a baby is a huge commitment," she said. "It's the only thing you can't get out of, like divorcing your husband or moving or selling your car."

"As I went through my pregnancy I became more in touch with the gravity of being a parent," Featherstone said. "I don't want life to be any harder than it is. I'm not carrying a special needs child full-term."

When she delivered the baby at home in 1998, the midwife noticed the classic low muscle tone, facial features and genetic bend on its finger. The baby was diagnosed with Down syndrome.

'I Was In It for the Long Haul

"To be honest, it wasn't what I was expecting," she said. "But I felt two things: She was the nicest human being I had ever met and whatever it took, it didn't matter. I was in it for the long haul."

Featherstone is fairly certain she would have taken the new Sequenom test had she been offered it early in her pregnancy. But now, with her 9-year-old daughter, Catherine, who brings much joy to her life, she is glad she didn't have that opportunity.

"She's a riot," said Featherstone. "She is so evolved in some areas and in others not so. But she is always raising awareness of the things closest to the truth. She has so much more clarity that those of us who are more socialized."

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