Down syndrome cells suppressed by scientists

U.S. researchers have discovered a way to disable the gene that causes Down syndrome, opening up new avenues for research and treatments.

In a study published Wednesday in Nature, scientists at the University of Massachusetts Medical School say they've found a way to suppress the effects of the extra chromosome that causes a genetic disorder affecting 500 Canadian newborns each year.

"Our hope is that for individuals living with Down syndrome, this proof-of-principal opens up multiple exciting new avenues for studying the disorder now, and brings into the realm of consideration research on the concept of 'chromosome therapy' in the future," said Jeanne Lawrence, the lead author of the study.

Humans are typically born with 46 chromosomes in each cell, but Down syndrome occurs when an extra copy of chromosome 21 is produced. This "trisomy 21" can lead to cognitive disabilities, early-onset Alzheimer's disease, infertility, shortened life expectancy and many other health effects.

Using lab-grown stem cells with Down syndrome, Lawrence's team spliced in an RNA gene called Xist, which normally functions to muzzle one of the two X chromosomes found in female embryos.

Xist functioned to modify the structure of the extra chromosome to deactivate most of its genes and prevent the production of proteins and other elements.

"It’s a strategy that can be applied in multiple ways, and I think can be useful right now," Lawrence said.