Special Services - DNA Grandparentage Test


A grandparentage test is used to determine whether a grandmother or grandfather is the true biological grandparent of a child. A grandparentage test is usually used when the parent of the child is not available for testing.

In situations where the alleged father is unavailable for testing (e.g. alleged father is deceased or unwilling to participate), the alleged father's parents can be tested to determine whether they are the true biological grandparents of the child. When conducting a grandparentage test, it is recommended to test both grandparents (the grandmother and the grandfather) in order to obtain the most conclusive results. If this is not possible, a grandparentage test can be conducted by testing only one grandparent.

The grandparentage test is not as powerful as the paternity test and as a result, you should proceed with grandparentage testing only if it is impossible to conduct a paternity test (e.g. alleged father deceased, or unavailable for testing.). Please read the information below to understand the benefits and limitations of grandparentage testing before proceeding.

Testing the Grandmother, Grandfather, and the Grandchild

When both grandparents are available for testing, there is a higher chance that you will receive informative results. When both of the alleged father's parents are available for testing, the laboratory will examine the genetic profile of both grandparents and then use the genetic information of the grandparents to reconstruct the genetic information of the missing alleged father. Once the alleged father's genetic information is reconstructed, a paternity analysis will be conducted by comparing the reconstructed genetic information for the missing alleged father against the genetic information of the child.

This test may detect when the grandparents are not the true biological grandparents of the child and has a high probability of providing informative results, even when the alleged father is not available for testing. If the child's mother can be tested, this will also increase the power of the grandparentage test. By testing the mother, the laboratory will be able to determine which half of the child's DNA came from the mother and thus focus the comparison of the remaining DNA from the alleged father to the DNA of the grandparents. As a result, the test becomes more discriminating. We would recommend that you first proceed by testing just the two grandparents because there is a chance that you will be able to receive conclusive results even without the mother. You can then bring the mother into the test later in the event that the grandparentage test is not powerful enough.

Testing only One Grandparent and the Grandchild

In some situations, only one grandparent is available for testing. When only one grandparent is tested, the missing alleged father's genetic information cannot be fully reconstructed. In such situations, the laboratory will test the single grandparent and the grandchild and then compare their genetic information. Based on the type of genetic material expressed by each individual, the number of genes which are shared, and the pattern of expression of the genetic material, the laboratory will be able to perform a statistical analysis to generate the "grandparentage index". If the grandparentage index is less than 1.00, this indicates that it is more likely that the grandparent and grandchild are not related. However, if the grandparentage index is greater than 1.00, this indicates that it is likely that the grandparent is biologically related to the grandchild.

This type of test is conducted when only one of the two grandparents is available for testing, and is not as powerful as testing both grandparents. Although there is a greater possibility when testing only one grandparent that a conclusive answer cannot be obtained, this test may be able to provide you with an indication of whether the grandparent is more likely to be or not to be the true biological grandparent of the child.

To proceed with grandparentage testing, please contact our laboratory at 1-888-262-2263.

Legal or Private Testing?

In most cases, clients who choose to proceed with grandparentage testing do not need to use the results in court and thus can proceed with a private sample collection procedure (home DNA collection kit). However, if you need to use the results of your grandparentage test as supporting evidence in court, you will need to call our laboratory to schedule an appointment for chain-of-custody sample collection. During the appointment, we will verify the identity of everyone participating in the test and witness the collection procedure. This method of sample collection is only required if you are using the results in court. The steps outlined below are for private knowledge testing.

Quick Facts

Test Type DNA Grandparentage Test, DNA Grandparent Test
Individuals Involved Grandmother, Grandfather (or both), and grandchild
Description To determine whether a grandmother or grandfather is the true biological grandparent of a child.
Fee for Private Home Test [?] $180 US for 1 Grandparent and 1 Grandchild
$275 US for both Grandparents and 1 Grandchild
Fee for Court-Admissible Home Test [?] $255 US for 1 Grandparent and 1 Grandchild
$350 US for both Grandparents and 1 Grandchild
Fee for Legal Test [?] $355 US for one Grandparent and 1 Grandchild plus specimen collection fees
$450 US for both Grandparents and 1 Grandchild plus specimen collection fees
Specimen Buccal swab (blood is also acceptable but not recommended)
Turnaround Time Regular: 3 to 5 business days, Express: 2 - 3 business days
Method of Reporting Mail, Email, or Telephone
Ordering This test can be ordered by phone, fax, mail, or online:
  • By phone: 1-888-262-2263
  • By Fax or mail: download a printable Order Form
  • Order online: order online 24 hours a day


Step 1 - Order the test. Order laboratory testing by phone at 1-888-262-2263 or by mail, or order the private DNA collection kit online.

Step 2 - Collect and submit the samples to the laboratory. Kits are delivered to your door within 24 hours by courier or within 5 working days by mail. Each Maternity test kit comes complete with all of the collection materials and instructions for you to take the test in the privacy of your own home. All Maternity testing kits employ the buccal swab technique, allowing you to perform the collection within minutes with no fuss, no pain. Submit the DNA specimen directly to the laboratory after collection.

Step 3 - Wait for results. Grandparentage test results are available within 3 to 5 working days (or as soon as 2 days for the express test) and can be obtained as soon as testing is completed using your secure order number and password online or by phone. Formal results documents are delivered to you by mail and / or E-mail. You may also call our laboratory to discuss your results over the telephone. To ensure the privacy and confidentiality of your case, we will confirm your password and file number before we discuss results over the telephone (the password and file numbers are provided to you when you order the test).

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