Relationship tests

Discover how much DNA you share

Relationship tests reveal shared genetic markers between two or more individuals — to confirm sibling relationships, grandparent lineage, or distant family connections.

Order the test How it works

Why a relationship test?

Unlike paternity tests, relationship tests rely on statistical probability ratios — the result expresses how likely it is that two people share a given relationship compared to a randomly selected person from the population. The higher the ratio, the stronger the evidence.

Shared DNA by relationship

Full siblings: ~50% shared DNA 50%

Half-siblings: ~25% shared DNA 25%

Grandparent/grandchild: ~25% shared DNA 25%

Uncle/niece or aunt/nephew: ~25% shared DNA 25%

Types of relationship tests

Siblingship test — full siblings

Compares DNA of two individuals claiming to share the same father and mother. The result confirms or excludes full siblingship and distinguishes it from a half-sibling relationship.

Inheritance disputes, identity verification from CZK 3,200

Siblingship test — half-siblings

Determines whether two individuals share only one biological parent. Typically used when there is doubt about a shared father or mother.

Confirmation of a shared parent from CZK 3,200

Grandparent–grandchild test

Determines the biological relationship between a grandparent and grandchild. Suitable when the potential father or mother is unavailable. Testing both grandparents is recommended for higher accuracy.

Inheritance, immigration proceedings from CZK 3,800

Avuncular test — uncle/aunt and nephew/niece

Confirms a biological avuncular relationship — between a parent's sibling and the child. Used as an alternative to a paternity test when the father is unavailable.

Substitute for unavailable parent from CZK 3,800

How does the test work?

Sample collection is identical to the paternity test — a buccal swab from the inside of the cheek. Samples from all tested individuals are sent to the laboratory, where shared STR markers are compared and the probability ratio is calculated.

✎ Tip: adding the biological mother to a siblingship test significantly increases the accuracy of the result.

When are relationship tests useful?

Confirming kinship for inheritance proceedings in court

Verifying family ties for international family reunification

Tracing biological family in cases of adoption

Personal interest in biological origins and genealogy

Medical history — hereditary conditions in the family

Need help choosing the right test?

We are happy to recommend the most suitable option based on your situation — free of charge and without obligation.

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