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Grandparent DNA Testing

Grandparent DNA testingwhen the father can't be tested.

Grandparentage testing compares a child's DNA with the alleged father's parents to establish a biological relationship — available for legal and personal purposes across Metro Atlanta.

Please note: Foxx Laboratories & Screening is a professional testing and collection company. We are not a hospital, urgent care center, or primary care medical clinic.

What a grandparent DNA test does

A child inherits half of their DNA from each parent, so a child's paternal grandparents share recognizable DNA markers with that child. When the alleged father is not available to test, comparing the child with his mother and father can establish whether the child is biologically related to that family line. Testing both grandparents — and including the child's mother — produces the strongest conclusion.

Because the comparison is indirect, results are reported as a probability of the grandparent relationship rather than the near-definitive figure a direct paternity test provides.

Who should be tested

  • • The child (cheek swab)
  • • One or both alleged paternal grandparents — both is stronger
  • • The child's mother, whenever possible, for a clearer result
  • • Photo ID for every adult participant in a legal test
Who it's for

Common reasons families test.

The alleged father is unavailable

When the alleged father is deceased, out of contact, incarcerated, or unwilling to test, his parents can be tested instead.

Legal, custody, and estate matters

Grandparentage testing collected under chain of custody with photo ID verification for court, child support, benefits, or estate questions.

Grandparents seeking answers

Grandparents who want to confirm a biological relationship with a grandchild for personal knowledge.

How it works

Four steps from call to results.

1

Call to plan the test

Call (833) 369-5227 so we can confirm who should be tested — one or both grandparents, the child, and ideally the child's mother. Appointments are required; we do not accept walk-ins.

2

Simple cheek-swab collection

Each participant gives a painless cheek swab that takes a few minutes. Adults bring photo ID for legal testing.

3

Accredited laboratory analysis

Samples are sealed under chain of custody and compared by an accredited laboratory to calculate the likelihood of the grandparent relationship.

4

Results and documentation

Results are released to the parties named on the paperwork, in legal or personal-knowledge format depending on how the test was ordered.

Appointments are required — call (833) 369-5227 before your visit so we can confirm participants and paperwork. We do not accept walk-ins.

Accuracy & common questions

How accurate is a grandparent DNA test?

A grandparent test compares shared DNA markers to calculate the probability of the relationship, so it reports a likelihood rather than the near-definitive result a direct parent-child test gives. Accuracy improves when both grandparents are tested and when the child's mother is included, because her DNA can be excluded from the child's profile.

Why should the mother be included?

Including the child's mother lets the laboratory subtract her contribution from the child's DNA, isolating the markers inherited from the father's side. That produces a much stronger conclusion about the alleged paternal grandparents.

Can only one grandparent be tested?

Yes, a single grandparent can be tested, but results are strongest with both paternal grandparents. If only one is available, adding the child's mother is especially important.

Is a grandparent DNA test valid in court?

It can be, when collected as a legal test — documented chain of custody with photo ID verification for every adult participant. Tell us up front that the test is for legal use so it is collected correctly; a home or personal test cannot be converted afterward.

What if a sibling or aunt/uncle is available instead?

We also perform sibling and aunt/uncle (avuncular) relationship testing. Call us and we will recommend the combination of participants that gives the clearest answer.

Do you offer at-home grandparent DNA test kits?

We perform collections in person at our Metro Atlanta location, and mobile collections can be arranged. In-person collection is what makes chain-of-custody and legal results possible.

See all DNA testing services or individual services.