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Good news for unborn babies and expectant mothers, a new less invasive procedure can safely determine if a fetus has Down Syndrome or other types of birth defects.  This test is a newly created blood DNA test.  Unlike standard tests like the amniocentesis and chrionic villus sammpling (CVS), this test carries no risk to the unborn baby.

Down syndrome is one of the most common childhood congenital defects.  It occurs when a fetus develops 3 copies of the 21st chromosome, rather than the normal 2.  This syndrome causes mild to moderate mental retardation.  Those with Down syndrome typically are physically characterized with poor muscle tone, short in stature, display of a single deep crease in the center of the palms, and an upward slant to the eyes.  Merely having Down syndrome can increase the risk for other medical conditions such as: congenital heart defects, respiratory, hearing difficulties, Alzheimer’s disease, childhood onset leukemia, and thyroid conditions.  Currently there are more than 400,000 people living with Down Syndrome.  One out of every 733 babies is born with the condition.

Stephen Quake, Ph.D., and Stanford University bioengineer from the Stanford University in California led a research team to make a way to look at small amounts of fetal DNA that circulated in the mother’s blood in order to find extra chromosomes that can cause Down’s syndrome and other birth defects. “We sequence millions of molecules from each blood sample nad map the DNA back to the chromosome and then we look to see if any chromosomes are over-represented.

This new test only requires a small blood sample from the mother.  This procedure is much safer than the traditional amniocentesis or CVS.  Both of the current traditional procedures are rather invasive and cause risk to the fetus.  Amniocentesis is done by inserting a needle into the uterus to examine amniotic fluid.  CVS actually requires a small amount of tissue being cut off the placenta for analysis.
This new procedure can also be done earlier in the pregnancy, as soon as 5 weeks after conception and the results are available within a few days.  The 2 more invasive methods are typically only done after the 15th week of pregnancy and it can take results 2-3 weeks to arrive.

In addition to being able to detect Down’s syndrome early, it can also detect other harmful conditions such as Edward syndrome.  This condition is caused by 3 copies of the 18th chromosome.  It happens in about 1 out of 3,000 pregnancies and 1 in 6,000 live births.  This condition carries an extremely low survival because of heart abnormalities, kidney malformations, and other disorders of the internal organs.

It can also detect  Patau syndrome, where an extra 13th chromosome is present.  This syndrome causes various phsical and mental deformaties, the most common being heart defects. This condition kills more than 80% of children during infancy.  It affects about 1 in every 12,000 live births