What is paternity testing?

Paternity testing can determine whether or not a particular man is the biological father of a particular child. This procedure involves collecting and examining the DNA of a small sample of bodily fluid or tissue from a child and the potential father.

DNA is the unique genetic "fingerprint" that makes up a person’s genes and chromosomes. When a baby is conceived, each parent passes on half of his/her DNA to the baby, whose genetic code (DNA) is a shared mix of only its mother’s and father’s DNA. By collecting and examining a small sample of DNA from the baby and the potential father, a paternity test can confirm or disprove that the man is indeed the biological father of the baby.

What bodily fluids and tissues can be sampled in a paternity test?

DNA is present in most of our body’s cells. A small sample for testing can be obtained from several bodily sources. The cells that are most commonly tested are obtained from the blood or inside the cheek of the mouth (called buccal cells).

How is the cheek cell test conducted?

Cells are collected by gently rubbing a cotton swab, similar to a Q-tip®, on the inside cheek of the alleged father’s mouth. The swab is sent to a laboratory, and a certain number of specific DNA sequences are examined to determine if the DNA collected from the baby match DNA collected from the alleged father.

How accurate is DNA testing?

DNA testing is generally considered to be the most accurate testing method available. DNA paternity testing can show that a man is highly likely to be the father with about 99.9% accuracy, or that he is excluded as being the father with 100% accuracy.

Can paternity be confirmed before the baby is born?

Technically, yes. Two different tests can be done while the baby is still developing in the mother’s womb. One test, called chorionic villus sampling (CVS), is conducted only between 11 and 13 weeks of pregnancy. This test involves testing a small sample of tissue from the placenta.

Another test, called amniocentesis, is usually performed between 16 and 22 weeks of pregnancy. This test involves passing a needle through the mother’s abdomen into the womb to collect a small sample of amniotic fluid (the “water” around the baby), which also contains cells from the baby. The collected samples are then sent to a laboratory for examination.

Although it is technically possible to confirm paternity with these tests, the risk of miscarriage – 1% (1 in 100) for CVS and 0.5% (1 in 200) for amniocentesis – leads most physicians to not offer CVS or amniocentesis for paternity testing only. People who have questions about this should speak with their physicians.

How long does it take to obtain paternity test results?

Results of buccal cell DNA paternity testing are usually available from the laboratory within 5 to 10 days. DNA paternity testing by CVS or amniocentesis take between three and four weeks before results could be made available.

Are home DNA paternity testing kits available?

Yes. Several laboratories offer home testing kits that can be purchased over the Internet. The kits contain all the necessary materials and instructions for conducting a cheek cell DNA swab test. After the cheek cells are collected, the sample is sent to the laboratory for analysis.

If the directions are followed correctly, the technique and accuracy of a privately conducted home test do not differ from a test required by a court order. For court-ordered testing, however, the potential father would need to report to a designated paternity testing facility so that the testing can be witnessed and fingerprints and photographs can be confirmed.

How can I locate a paternity testing facility?

The AABB (formerly known as the American Association of Blood Banks) is an organization that provides accreditation for laboratories offering relationship testing (including paternity testing). Accreditation means that each laboratory listed has met specific standards for testing accuracy and service. For a list of AABB-accredited relationship testing facilities, please visit http://www.aabb.org/sa/facilities/Pages/RTestAccrFac.aspx.

Can the results of a home paternity test be used in a court of law?

Without legal identification of the test taker and official witnessing of the test, a home paternity test is not admissible in court.

How much does a paternity test cost?

Tests costs vary from less than $100 for some home kits to more than $500 for the complete testing process through an accredited facility. Prenatal paternity testing is usually much more expensive because of the ultrasound, CVS or amniocentesis procedure, and doctor fees. You will need to contact your nearest facility to get a cost estimate.


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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 6/20/2017...#10119