DNA Paternity Test

What is a DNA paternity test?

A DNA paternity test uses deoxyribonucleic acid (DNA) — usually taken from a cheek swab — to determine a child’s biological father (non-birthing parent).

DNA is the genetic material inside your body’s cells. It acts like an instruction manual to help make you who you are. You inherit DNA from both of your biological parents — half from each parent. “Paternity” refers to the non-birthing parent.

Why do people need DNA paternity tests?

Establishing paternity is important for many reasons, including:

• Gaining legal rights to child support, child custody, Social Security benefits and inheritance.
• Identifying links to genetic disorders that can affect your long-term health, including cystic fibrosis, Down syndrome and certain types of cancer.
• Helping a child learn more about their family history.

When is a DNA paternity test performed?

A healthcare provider can perform a prenatal (during pregnancy) DNA paternity test as early as the eighth week of pregnancy. Postpartum (after a baby is born) tests are also available.

How does the test work?

A DNA paternity test collects tissue or blood samples from:

• The birthing parent.
• The potential non-birthing parent.
• Sometimes, the fetus or the child.

Lab technicians analyze the samples and look for genetic markers — characteristics in the DNA sequences — that the fetus or child shares with the pregnant person or person who gave birth and the potential non-birthing parent.

What to expect before a DNA paternity test?

Most DNA paternity tests use a cheek swab to collect a DNA sample from the potential father. They’ll use a cotton swab to collect cheek (buccal) cells from the inside of your mouth. At least an hour before the cheek swab, it’s a good idea to avoid:

• Brushing your teeth.
• Using mouthwash.
• Putting in dentures.
• Smoking or using chewing tobacco (dip).

These may affect the quality of your cheek swab.

In some cases, a DNA paternity test may require a blood sample. Before a blood test, a provider may recommend that you:

• Drink extra fluids.
• Eat healthy foods.
• Moisturize your arms.
• Do some gentle exercises to help boost your blood pressure.

If you’re pregnant, you may need an ultrasound before a DNA paternity test to confirm how far along you are in your pregnancy (gestational age of the fetus).

What are the types of DNA paternity tests?

The types of DNA paternity tests include:

• Noninvasive prenatal paternity (NIPP) test. An NIPP test analyzes fetal DNA in the pregnant person’s blood. A provider will take a blood sample after your eighth week of pregnancy. They send the samples to a lab, where a specialist analyzes trace amounts of the fetus’s DNA in the blood sample and compares it to the DNA in a cheek swab from the potential non-birthing parent. An NIPP is 99.9% accurate and very safe. Risks include pain, bleeding, bruising, fainting and infection.
• Amniocentesis. Amniocentesis is an invasive prenatal test that can occur during your second or third trimester (15 to 20 weeks). A provider will use a thin needle to take a sample of the amniotic fluid that surrounds the fetus. The procedure takes place through your abdomen. They’ll then compare the sample to the cheek swab DNA of the potential non-birthing parent. Amniocentesis risks are rare but may include miscarriage or premature labor.
• Chorionic villus sampling (CVS). A CVS test is similar to amniocentesis. It typically occurs 10 to 13 weeks after your last menstrual period. A provider will use a thin needle to remove a small sample of chorionic villi cells from the placenta. The procedure takes place through your cervix or abdomen. A lab specialist will compare the sample to the cheek swab DNA of the potential non-birthing parent. Risks are rare but include miscarriage and infection.
• Cheek swabs. The potential non-birthing parent and child swab the inside of their cheeks for buccal cells. You mail the cotton swab applicators to a designated lab for analysis. If swabbing takes place in a medical setting, the office sends the samples to a lab for analysis.

What are the risks of a DNA paternity test?

It depends on the type of test. A healthcare provider will thoroughly explain all the risks and answer any questions you may have.

How long does it take?

• Cheek swabs take less than a minute.
• A blood draw takes a few minutes.
• Amniocentesis takes about 10 minutes.
• CVS takes about 10 minutes.

How can I do a DNA paternity test at home?

For an at-home paternity test, you purchase a kit that contains:

• Cheek swabs.
• Collection tubes or storage envelopes for the cheek swabs.
• A mailing envelope.

The potential father and child use the cheek swabs to get DNA samples. They then seal samples in collection tubes or envelopes and mail them to a lab. It typically takes a week or two to get your results.

What are the pros and cons of an at-home DNA paternity test?

At-home paternity tests are usually cheaper than one you would get at a testing facility. However, the results of an at-home paternity test may not be as accurate, and they aren’t admissible in court. Look for a testing kit that analyzes more genetic markers — the industry standard is 16, but some at-home tests analyze more. The higher the number, the more accurate the results.

Before you purchase an at-home DNA paternity test, it’s a good idea to ensure it meets strict standards for testing and accuracy. Look for accreditation from the American Association of Blood Banks (AABB) or another standardization organization.

What type of results do you get, and what do the results mean?

DNA paternity test results usually list a “probability of paternity” as two values: 0 or 99.9.

A result of 0 means there isn’t a genetic match between the potential non-birthing parent and the fetus or child — they aren’t the father.

A result of 99.9 means that the potential non-birthing parent is very likely to be a genetic parent of the fetus or child.

When should I know the results of a DNA paternity test?

It depends. The turnaround times for some labs may vary from others. In general, it usually takes a few days to get the results. But it can take up to several weeks to get paternity results from CVS or amniocentesis paternity tests. For an additional fee, some businesses offer same-day or one-day results.

At-home DNA paternity test results usually take a week or two to get results after your samples arrive at the lab.

Can I use a DNA ancestry test to prove paternity?

No. An ancestry DNA test can identify potential DNA matches. But only a DNA paternity test can prove a DNA match between a child and a non-birthing parent.

How much is a DNA paternity test to see who the father is?

It depends on what type of DNA paternity test you get. At-home tests may range from $15 to $200, plus the cost of a lab fee and any shipping and handling fees. Lab fees typically cost over $100.

A DNA paternity test in a medical setting costs more — up to $500. Health insurance doesn’t cover the costs of a DNA paternity test.

Can a DNA paternity test be done without the father?

The most accurate way to conduct a DNA paternity test is with the potential non-birthing parent’s DNA sample. If they’re deceased, you may be able to get a sample from a medical facility, coroner’s office or medical examiner’s office. If they’re missing or unavailable, it might be possible to get or use a sample from their biological parents, grandparents, aunts, uncles or siblings. Close biological relatives share a lot of the same DNA.

How do I get a paternity test in NY?

The New York State Department of Health doesn’t allow at-home DNA paternity tests. You must go to an approved facility to take a DNA paternity test.