Genetic Testing Prenatal

DNA and genetic testing stories are commonplace in today’s media. Genetic testing has solved crimes, the perpetrator being convicted by DNA evidence left at the scene of the crime. Fathers are publicly identified on national television through DNA an prenatal paternity testing.

We hear of people making life or death decisions regarding their unborn children because of the results of prenatal genetic testing, and how prenatal testing issues affect abortion and other medical issues. We’ll talk about prenatal testing, why and how it’s done, and the risks and benefits of performing these tests.

History of DNA and Genetic Testing

In 1935 DNA was isolated, and in 1953 scientists had designed the double-stranded helix model we see in textbooks and on videos. Scientists began cracking the genetic code as early as 1966. By 1984 identification based on genetic profiles was added to law enforcement forensic arsenals. In 2000 The Human Genome Project announced they had completely sequenced the three billion chemical pairings in human DNA.

So the technique of DNA testing is relatively new, but very effective. Used in prenatal genetic testing, DNA profiles have become vital for parents who need to know the condition of their unborn child.

Reasons for Prenatal Genetic Testing

Parents choose prenatal genetic testing for several reasons:

  • prenatal paternity testing
  • gene abnormalities
  • gender identification
  • chromosomal abnormalities
  • possible donor material for family members
  • decisions regarding the future of the pregnancy
  • other genetic markers such as deafness, early-onset Alzheimer’s, some cancers, and arthritis.

Prenatal testing has long been encouraged in the second trimester for mothers over the age of 35. It is now recommended that all pregnancies be tested because there are new and promising procedures that may correct some abnormalities and conditions in utero.

Prenatal Testing and Abortion

Prenatal testing and the resulting decisions made by the parents are controversial ethical and moral issues. Many parents, when faced with a severe abnormality, may choose to abort the pregnancy. Earlier, Down’s Syndrome was diagnosed in the second trimester in older mothers. Now prenatal testing and diagnosis can reveal the condition in the first trimester, allowing the parents to discuss options and make a decision earlier in the pregnancy.

Types of Prenatal Genetic Testing

Two specific tests, amniocentesis and the Chorionic Villus Sampling (CV) are often used during pregnancy to test a baby’s DNA, and timing is essential. The first window for testing is between the tenth and thirteenth week of pregnancy, and is when the CV test is usually done. In this procedure, a needle is inserted up through the cervix and a small tissue sample is taken from the uterine wall (this material has the same DNA as the baby). There is minimal risk with this procedure.

The second window for prenatal testing is between the fourteenth and twentieth week of pregnancy when amniocentesis can be performed. This is a procedure where a very thin needle is guided into the uterus and amniotic fluid is then extracted and tested for DNA. There is a slightly higher risk to the mother and baby with this procedure.

Unless the mother and baby are at risk, the costs usually run between $1,000 and $2,000 per test procedure and may not be covered by insurance. It takes a doctor’s order to get either one of these prenatal tests done.

Developments in Prenatal Testing

A new prenatal test is in development that uses fetal DNA in the mother’s blood to accurately diagnose or rule out genetic defects as early as the first trimester. Taking a sample of the mother’s blood would be much less invasive than either an amniocentesis or a CV test and results would come faster and earlier in the pregnancy. This non invasive test should be ready for final testing soon.

The Morality of Prenatal Genetics Testing

It is a moral and ethical issue that every parent faces; if we get bad news, what do we do about it? Parents, religious leaders, disability rights advocates, and pro life advocates weigh in heavily on this issue. Prenatal testing and abortion is a particularly heated topic.

Regardless, the bottom line is that parents can have peace of mind early if the prenatal testing and diagnosis of abnormality is correctable in utero (and more and more are), and plans can be made for whatever the future holds.

Resources

Harmon, A. May 13, 2005, Genetic testing abortion = ???. Retrieved September 18, 2008, from the New York Times Web site: nytimes.com/2007/05/13/weekinreview/13harm.html.

Jongsma, J. (2007). DNA Files: Prenatal genetic testing: Do you really want to know your baby’s future? New