dadcheckgold - DNA testing services

Call us today:

0191 543 6334

0203 603 1323

DNA Tests for Other Relationships

DNA Tests for Other Relationships

We offer other human relationship DNA tests for siblings (half/full brother/sister), avuncular (aunt/uncles) and grandparentage.
You may order a complex relationship DNA test by telephone only. To download a contact us / quotation form click here.

Sibling Testing

Sibling DNA testing is used to determine whether two individuals have biological parents in common, when one or more of those parents are not available for testing.
That is, are two individuals related as either full or half brother or sister.
Sibling DNA testing can be used in a number of different scenarios, for example, to provide evidence towards paternity when the alleged father is deceased, re-uniting relatives separated through adoption and in particular, aiding disputes over inheritance.
dadcheck®gold is able to provide DNA testing services to determine whether two people are related as:
  • Full siblings: i.e. they share the same biological mother and father
  • Half siblings: i.e. they share only one biological parent
On average full siblings will have more DNA in common than half siblings and similarly, half siblings will have more DNA in common than unrelated people. The statistical analysis performed following the generation of unique DNA profiles will determine the most likely relationship based on the DNA profiles generated.
Please note: As a sibling test is trying to ascertain the existence of a biological relationship with another person without actually testing their DNA directly i.e. the shared parent(s) it is not as conclusive as a paternity test. As such, if any one of the parents of either of the potential siblings who are being tested is also available and willing to take part in the testing, we strongly recommend that they participate as this enhances the statistical analysis and could improve the end result. Sibling tests conclude which is the most likely relationship given the DNA evidence generated.
We will provide any necessary consent forms and give advice on these matters at the time of ordering.

Avuncular (Aunt/Uncle) Testing

This type of DNA test enables to prove evidence of family relationships if an alleged father is not available for testing. It is dependent upon the alleged father and his brother/sister sharing markers and for these to be inherited by the child.
Needless to say, these types of test are not conclusive and only give an indication of the likely relationship. It can become especially complicated if for example, we are not sure of the precise relationship between the alleged father and his brother/sister. So we may not be able to detect a relationship, even if one actually exists.
These caveats will be explained fully in any report we deliver.
We are often asked to ascertain the relationship is one of cousins. The genetic relationship is not close enough for meaningful data to be derived and as such, we do not carry out such tests.

Grandparentage (Grandmother/Grandfather) Testing

DNA testing can be used to examine the relationship between a child and a possible grandparent. Such tests are often performed when the potential father (or mother if you are trying to determine maternity) is unavailable for paternity testing.
As with sibling tests, DNA profiles will be generated from the samples donated and then compared using statistical analysis to determine the most likely relationship between the child and grandparent(s), if any.
Testing options:
  • Best option – Child + one parent + both grandparents
    DNA testing using paternal grandparents should ideally include samples from the child’s mother as well as from both paternal grandparents. This will provide the same degree of certainty as if a sample from the alleged father had been tested. The same principles can be applied to prove maternity, by testing the child, father and both maternal grandparents.
  • Next best option – Child + one parent + one grandparent
    If the parent and only one of the grandparents are available, the test will provide a strong indication of whether the child and grandparent are related but it cannot provide a conclusive result.
  • Last option – Child + one grandparent
    It is possible to just compare the DNA profile of a child and an alleged grandparent, although we can strongly recommend that the available parent of the tested child is always tested. This can provide an indication of an existing biological relationship but, because of the patterns of DNA inheritance, it will not always reveal the true nature of the relationship. Such an analysis can only report the most likely relationship based on the DNA profiles generated.
If you would like to discuss a case, request a quotation or place an order, please feel free to call us on either 0191 543 6334 or 0203 603 1323 or send an e-mail to We will be pleased to answer any questions you may have and to advise on the best testing scenario for your client(s).
For the time being, we only take telephone orders for complex relationship testing cases.

Download a Quotation Form Here

Please return the completed downloaded form by either;
  • a) e-mail to,
  • b) mail to Complement Genomics Ltd (dadcheck®gold), The Durham Genome Centre, Park House, Station Road, Lanchester, Co. Durham, DH7 0EX.

We are one of only a few companies in the UK which are able to provide a DNA testing service suitable for legal purposes. The dadcheck® service is accredited by the Ministry of Justice as a body that may carry out parentage tests directed by the civil courts of England and Wales under section 20 of the Family Law Reform Act 1969.

© Complement Genomics Ltd.

Registered Office: The Durham Genome Centre, Park House, Station Road, Lanchester, Co. Durham, DH7 0EX.

Registered in England No. 3929876.