Skip to main content
  1. Life
  2. Health & Fitness
  3. Healthcare

Turning off the extra chromosome in Down syndrome

See also

Scientists have discovered a way to silence the genes on the third copy of chromosome 21 that causes Down syndrome. The results of the study were published on July 17, 2013 in the journal Nature.

More Photos

In Connecticut, an estimated 40 to 50 babies are born with Down syndrome each year (about 6,000 babies in the U.S. each year). That’s about 1 in every 700 babies born. According to the Connecticut Down Syndrome Congress, there are an estimated 3,000 people in Connecticut with Down syndrome (personal correspondence).

Normally, human cells contain 23 pairs of chromosomes. One chromosome in each pair comes from the father, the other from the mother. People with Down syndrome are born with an extra copy of chromosome 21. This extra genetic material changes way the body and brain develops and is responsible for the characteristic features and developmental problems of Down syndrome.

Researchers at the University of Massachusetts Medical School have silenced the extra copy of chromosome 21 in a model of Down syndrome. They used an enzyme to introduce an RNA gene (called XIST) into cultured stem cells from Down syndrome patients. The XIST RNA coated the extra third copy of chromosome 21, silencing the genes on it. This helped correct the unusual patterns of cell growth and differentiation seen in Down syndrome cells.

The study was inspired by a naturally occurring event – during development, XIST switches off one of the two X chromosomes in female embryos, ensuring that daughters do not express a double dose of X chromosome genes.

This study was performed in the laboratory on a cell culture model of Down syndrome. However, the results provide a step towards ‘whole chromosome therapy’ for disorders such as Down syndrome and will help scientists understand the basic biology underlying this disorder. This research also provides a model to study normal chromosome silencing.

To receive e-mail alerts when new articles by the Hartford Health Examiner become available, click on "Subscribe" at the top or bottom of the page. It's anonymous and completely free.

Advertisement

Life

  • Dan Savage
    Dan Savage cares about LGBT youth, bullying and saving lives
    Today's Buzz
  • Raku
    Teachers and students can use this summer to learn a new skill
    Camera
    15 Photos
  • Beach body
    Fitness: Earn your beach body badge with bootcamp classes
    Camera
    10 Photos
  • Greek wine
    Unwind with these delicious wines: The thrilling wines of Greece
    Camera
    7 Photos
  • Mandy Moore
    Exclusive interview with Celebrity Mandy Moore concerning animal activism
    Camera
    5 Photos
  • Educational family vacations
    Find out how to take an educational family vacation that doesn't break the bank
    Camera
    9 Photos

Related Videos:

  • Applying mosquito repellent
    <iframe width="560" height="315" src="//www.youtube.com/embed/cM1YI5TuljA?rel=0?rel=0&amp;VQ=HD720&amp;allowfullscreen=true&amp;autoplay=1"></iframe>
  • MMR vaccine in vial
    <div class="video-info" data-id="518296047" data-param-name="playList" data-provider="5min" data-url="http://pshared.5min.com/Scripts/PlayerSeed.js?sid=1304&width=480&height=401&playList=518296047&autoStart=true"></div>
  • Musician/Actress Janet Krupin
    <iframe width="560" height="315" src="//www.youtube.com/embed/UMS0K0LlmqE?VQ=HD720&amp;allowfullscreen=true&amp;autoplay=1"></iframe>