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Can a DNA Test Prove Grandparent?
Updated on September 15, 2022
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Can a DNA Test Prove Grandparent?
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Most people use DNA tests to identify a biological parent or learn more about their heritage in general.

But it’s also possible for grandparents and grandchildren to determine a genetic link using DNA. The results aren’t as accurate as they are with a closer relative, but a DNA test can prove a grandparent.

Can a DNA Test Prove Grandparent? 2

Why Take a DNA Test to Prove a Grandparent Grandchild Relationship?

There are several reasons people do genetic testing for grandparents and grandchildren.

These include: 

  • Alleged biological father isn’t available for testing
  • Need to establish legal grandparent rights
  • Desire to learn more about genetic history and one or both parents aren’t available
  •  Need to establish a genetic link for inheritance concerns
  • Peace of mind

Grandparents, grandchildren, or the legal system can all initiate tests with proper permission.

Some courts grant special rights to grandparents in terms of custody and/or visitation. However, the court requires a biological link to be established before it will consider doing so. Keep in mind, if a legal adoption occurred, any potential grandparent rights were severed at the time of placement.

How Do Grandparent DNA Tests Work?

Grandparent DNA tests are similar to standard parental tests, but they require more genetic input for the best results.

The more genetic material the lab has to evaluate the more accurate a profile they can provide.

Ideally, DNA samples will come from:  

  • Grandchild  
  • One or both grandparents
  • Grandchild’s biological mother

Obviously, this won’t be possible in every situation, but it’s the best way to create the most complete genetic picture. Testing both alleged grandparents leads to the most accurate test results, but it’s possible to administer a test with only one grandparent’s sample. 

In the latter example, the test might not be enough to establish legal paternity or maternity or to lead the court to grant grandparent rights, but each situation is different.

What Type of Sample is Used in a Legal Test?

The most common type of DNA sample is a buccal swab. Samples are collected using a cotton swab that is gently rubbed on the inside of the cheek.

Blood samples are also an option.

Keep in mind that most at-home testing doesn’t provide results that will hold up in court. Make sure you speak to an attorney or the court to determine what is needed from you before taking a test to establish a genetic link in a grandparent DNA test.

Additionally, if you are not the grandchild’s biological parent or legal guardian, you must obtain all necessary consent before gathering and submitting his or her DNA for testing.

As a grandparent, you have no right to demand a DNA test. You can ask and hopefully, your request is approved, but if not, there is little recourse because you are not directly a part of a paternity action.

Mandatory DNA testing requires a court order signed by a judge. This is the only way you’ll be able to obtain a DNA sample against a parent or guardian’s wishes and it’s usually difficult for a grandparent to obtain such an order.

Your goal should always be to aim for the most accurate and comprehensive results possible, however that looks for you, regardless of your reason for taking a test.

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Why Do Grandparents Need DNA Testing?

Both alleged grandchildren and grandparents might want to conduct a DNA test to establish a genetic relationship. And in both cases, there might be legal reasons for doing so.

For grandparents, visitation rights can be an option if you can establish a genetic link to a child.

This is sometimes the case when the child’s biological parent denies grandparents the right to see the child. Laws vary from state to state and courts tend to err on the side of honoring the wishes of a parent over a grandparent, but there are situations in which grandparents can be legally granted the right to be a part of their grandchild’s life. 

Establishing a genetic link is the first step in achieving this goal.

An alleged grandparent might also want to eliminate the suspicion of a genetic link with a grandchild for estate planning purposes. If someone claims to have a legal right to inheritance based on a genetic relationship, one needs only prove this link to be false to remove any estate rights.

Remember, estate planning documents such as a will or trust would override genetic links in most cases.

A person can decide to leave their possession to whomever they choose genetic link or not. But if a person dies intestate and the probate court is forced to make decisions about the distribution of inheritance, it will do so based on legally established relationships.

Likewise, to be entitled to inheritance from someone you believe to be your biological grandparent, you’ll need to find a way to establish this relationship as valid in the court’s eyes. DNA testing plays a role in accomplishing this.

Can a DNA Test Prove Grandparent Genetic Links?

Yes, but the results of a grandparent DNA test are usually not 100 percent accurate.

DNA testing provides information about the likelihood of a genetic link and because so much of our DNA comes from our four grandparents, we can gain a great deal of information by using this type of testing.

Suppose you need to establish a genetic family relationship between yourself and a grandparent or you and a grandchild, or to establish paternity when the biological father is not available for testing. In that case, a grandparent DNA test is an option.

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  1. “Summaries of State Law: Grandparent Visitation and Custody.” Findlaw, Accessed 20 Nov. 2020.
Cristine Santander
Cristine Santander
Content Contributor
Cristine Santander is a content writer for KnowYourDNA. She studied B.S. Psychology and enjoys writing about health and wellness.
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