This non-invasive prenatal test for Down syndrome would replace amniocentesis, which uses amniotic fluid extracted from the uterus and can cause complications including infection and miscarriage, scientists from Stanford University and the Howard Hughes Medical Institute say.
The team of researchers led by Stephen Quake of Stanford University in California took a small blood sample from mothers to look for the extra chromosomes that cause Down's and similar birth defects.
Down's syndrome, which causes mental retardation and other problems, is caused when a child has three copies instead of the normal two of chromosome 21. The mother's blood contained a tiny proportion that comes from the fetus.
The method helped them to detect excess genetic material from a specific chromosome, indicating a problem. It also detects other chromosomal and often lethal conditions such as Edwards syndrome and Patau syndrome.
A biotechnology company in San Diego called Sequenom says it will begin selling such a test next June, New York Times reports. In 2007, U.S.-based company Ravgen announced the successful trial of a similar detection method. San Diego-based Sequenom is also working on a Down's blood test using a different approach.
