DNA Tests Available > Grandparent DNA Testing
A grandparent DNA test can be used to determine whether a child is biologically related to a potential grandparent or set of grandparents. This test is usually used when the alleged father of a child/individual is unavailable for paternity testing. If the alleged father is available for testing then a Paternity DNA test should be used rather than the Grandparent DNA test.
The test analyses genetic locations on the DNA strand to create a DNA profile for each test participant. The DNA profiles of the test participants are then compared.
A grandparent DNA test is based on the laws of DNA inheritance through a family line. At conception a child inherits half of his or her genetic DNA profile from each of their biological parents.
The DNA passed onto a child from their father has in turn been inherited from the father’s parents. This is the same for the child’s mother. Due to this, biological grandparents will have DNA in common with their biological grandchildren.
When one of a child’s parents is unavailable, missing or deceased, it is possible to test the DNA of the grandparents to determine if they have contributed to the child’s DNA profile through their son or daughter. This contribution is presumed to be through the absent father (if it is the paternal grandparents that are tested).
If the DNA test is being used to establish who the father of a child is, then the potential paternal grandparents must be used i.e. the parents of the unavailable father.
The grandparent DNA test can also be used to find the biological mother of an individual. This is usually used in adoption cases and for this the potential maternal grandparents should be used.
The DNA test result is based on complex statistical analysis which looks at many factors. These include how many DNA markers match between the test participants and how popular those markers are within a given population. Calculations are performed based on the relationships being tested.
The values from the calculations are used to generate a percentage probability value. The percentage probability will indicate which relationship is most likely to exist.
There are typically four types of Grandparent DNA Test, depending on the situation:
In the above four types of Grandparent test, the analysis of the DNA profiles will determine which if the likelihood of;
At DNA Clinics, a clinical advisor will work with you to establish exactly what the situation is and what the known facts are, thus determining the correct form of DNA test for your family.
Single Grandparent DNA Study:
To establish the biological relationship between an individual and one alleged grandparent.
Examples of this study include:
Duo Grandparent DNA Study:
To establish the biological relationship between an individual and both alleged grandparents.
Examples of this study include:
We always recommend that a DNA sample from the grandchild’s mother is included for testing as this can strengthen the DNA test result. The mothers DNA sample will be processed for free.
DNA tests carried out between potential grandparents and a grandchild are usually a way of testing the identity of a biological parent, without directly including that alleged parent in the test. This most commonly occurs when an alleged father is not available for testing or is unwilling to be tested. In these cases, the paternal grandparents are used in his absence.
Although Grandparent tests can be very accurate and useful DNA tests, they cannot replace the tests that directly test the DNA of a biological parent. For example, if an alleged father is available for testing, then a Paternity DNA test should be used rather than a Grandparent test.
If a Paternity test is not available, then other tests should also be used. If the alleged father has another – undisputed child, then a sibling DNA test can be performed. In some instances, where both test participants are male, testing using another type of DNA test called a Y-chromosome test may provide useful evidence of the relationship. This type of test can confirm conclusively that two males do not share the same father or that the two males belong to the same paternal line.
While these tests can provide accurate results, there is a chance that the test will yield an INCONCLUSIVE result.
Inconclusive results are not the same as negative results. Inconclusive results mean that the laboratory analysis cannot determine the answer to the question posed by the client.
An INCONCLUSIVE result occurs in 25% of Grandparent DNA tests (i.e. 1 in 4).
All of the DNA markers that show matches between test participants are very common within the relevant general population. In these circumstances the matches do not provide the required genetic evidence to confirm which biological relationship exists.
There is a low level of DNA matches between the DNA profiles of the participants due to the chance nature of inheritance in families.
Where matches may have originally occurred, mutation has changed the DNA marker and caused mismatches at further locations within the DNA profile.
The grandparent DNA test can be used to answer the following questions:
For your Grandparent DNA Test, DNA Clinics also provide professional sample collection for peace mind tests as well. Call DNA Clinics today to discuss making an appointment at a DNA Clinic today.
A convenient home visit service is available for the collection of your DNA samples. This may be of particular use if there are elderly test participants involved in the case. Call DNA Clinics today to discuss home appointment options.
As mentioned above, this sample collection option could be of use to elderly DNA test participants. Call and order a Home DNA Test Kit today for your Grandparent test analysis or visit our on-line store and order your FREE DNA Grandparent test kit.