Scientists work on cure for Down syndrome

Scientists work on cure for Down syndrome

By Karen Kaplan

Los Angeles Times

Scientists are hard at work developing a cure for the genetic disorder Down syndrome. But even if they succeed, nearly 60 percent of parents whose children have Down syndrome might take a pass.

In a survey conducted by researchers from the psychiatry department at the University of British Columbia in Vancouver, 27 percent of parents said they would not cure their children, and another 32 percent said they were unsure. Many parents expressed concern that a cure would change their child’s personality, said Angela Inglis, a genetic counselor who worked on the survey.

“Yes, it is a challenge, but your life will change in so many ways for the good, (but) you can’t imagine not having him,” said one parent who would decline a cure.

That feeling was not universal. Forty-one percent of parents said they definitely would treat their children for Down syndrome. Those parents said they were motivated by a desire to make their kids more independent and to give them more opportunities in life, Inglis said. She added that parents who had the hardest time caring for their children were the most inclined to seek a cure.

“It is very difficult, especially for the family dynamics,” one parent told researchers. “It changes our life because there is so much more stress and issues with a child with special needs. We often feel like giving up on life.”

Patients with Down syndrome have three copies of chromosome 21 instead of the usual two. In addition to the mental and physical symptoms, it can cause congenital heart disease, hearing problems, celiac disease, dementia and problems with the intestines, eyes, thyroid and skeleton. People with Down syndrome often live into their 50s, according to the National Institute of Child Health and Human Development.

About one in every 800 babies is born with the disorder. Pregnant women over the age of 35 are routinely offered prenatal screening for Down syndrome. Nearly two-thirds of parents surveyed said they thought prenatal testing for the disorder — through amniocentesis or chorionic villus sampling — was a “good thing,” and 60 percent said such testing should be available to pregnant women of any age.

The survey was conducted in Canada and included responses from 101 parents. No similar surveys have been taken in the U.S. The results were reported this week at the National Society of Genetic Counselors’ annual education conference in Atlanta.

The question about a cure might become less theoretical in the not-too-distant future.

In patients with Down syndrome, the brain loses its ability to make an important neurotransmitter called norepinephrine. But researchers from Stanford University and the University of California, San Diego found that in genetically engineered mice that have a rodent version of the disease, injections of a drug called xamoterol returned the animals to normal function.

Once inside the mouse brains, xamoterol converted into norepinephrine and allowed the mice to build nests and complete cognitive tests just like regular animals, according to a study being published in Thursday’s edition of Science Translational Medicine. The drug kicked in within just a few hours, but its effects wore off quickly.

The researchers suggested that people with Down syndrome could be treated with Droxidopa, another drug that converts into norepinephrine in the brain. Droxidopa is taken by people for orthostatic hypotension in Asia, and it’s in Phase 3 clinical trials in the U.S. It should be taken with a second drug called carbidopa that would keep it from converting to norepinephrine until it entered the brain, the researchers said.