Advances in a DNA diagnostic center allow a new method of DNA fingerprinting. It comes from a single drop of a mother’s blood.

This new method of testing can show a mother-to-be if her unborn child has an inherited condition such as cystic fibrosis. Best yet, the blood sample eliminates the need for risky amniocenteses in which the uterine wall is punctured for retrieval of umbilical fluid.

Because a pregnant woman’s blood has her own DNA plus that of her unborn child, doctors can search for markers of a host of genetic disorders developing in her fetus.

Cystic fibrosis comes from a recessive gene which can come from the mother and her father. So far, no test has worked perfectly however a new technique called digital polymerase chain reaction, or dPCR, is narrowing the likelihood of cystic fibrosis in the unborn by allowing doctors to count the number of copies of the recessive gene in the blood sample of the pregnant woman.

Scientists are excited about this new test because it is the most accurate predictor yet of disease in an unborn child. More testing needs to be done before dPCR can be widely administered.

The dPCR is expected to draw controversy among right-to-life supporters. Though the incidence of miscarriage is expected to go down with this new, safer way of testing without breaching the uterus, some fear more women will abort their defective fetuses. Pro-life advocates argue children born with Down ’s syndrome have a better prognosis today and should not be terminated from the womb once a pre-birth diagnosis is made.

Ultimately the dPCR screening test will be yet another tool of information so that expectant parents can make choices involving their families in a knowledgeable way. It’s one advance in the rapidly changing world of a DNA diagnostic center and its services.