DNA Relationship Testing

easyDNA South Africa offers DNA relationship testing priced from only R3295. Relationship testing can be used to assess if two or more people share a biological relationship. In situations where the alleged parents are unavailable for testing, a sibling test can be done to analyse the relationship of biological siblings through direct comparison with their alleged relatives.

Relationship testing is slightly more complex than paternity testing and can be used to determine various types of relationships in different situations.

Complete list of DNA relationship tests

Depending on the people available for testing, there are several different testing methodologies that can be used according to the alleged relationships. An explanation of the various DNA testing methodologies is provided below.

Sibling DNA testing                       Order Now

Sibling testing is ideal in situations where two alleged siblings want to confirm their biological relationship and verify if they are full or half siblings or possibly not related at all. The DNA sibling test can be conducted with or without the parent’s sample.

easyDNA can confirm if two people are related by sharing one or both parents, meaning that they are either full or half siblings. In the case of half sibling testing, the sample of the known parent/s (normally the Mother) is recommended to strengthen the results of the test if available.

• In cases where siblings are male, and want to determine that they share the same father, we recommend using a Y-chromosome test. This test is able to determine male lineage. For further information on this type of test, visit our Y-chromosome testing page.

• In cases where siblings are female, and have different mothers, an X-chromosome test can be used to determine if they share the same father. Visit our X-chromosome testing page for more information on this test.

• If siblings are either sex and wish to confirm maternal lineage, then an mtDNA Test can be used. Please visit our mtDNA testing page for further details on this test.

• If you want to confirm if two siblings are fraternal or identical twins you can select a twin zygosity test.

Siblingship testing is priced from R3295. Results are available in 5-7 working days receipt of samples at the laboratory.

DNA testing: grandparentage DNA test            Order Now

In situations where the alleged father is unavailable for testing such as he 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. If so, the sample of a common parent (normally the Mother) must be included to strengthen the results of the test.

The Grandparentage test is priced from R3295. Results are available in 5-7 working days from receipt of samples at the laboratory.

Aunt/uncle DNA testing / avuncular DNA test           Order Now

Avuncular DNA testing assesses whether an individual is the aunt or uncle of another person. This type of case is often used when the alleged parent of the person is deceased and/or unwilling to participate in testing and a brother or sister of the alleged parent is still alive and available for testing. The sample of the mother is recommended to strengthen the results of the test but is not necessary.

Avuncular testing is priced from R3295. Results are available in 5-7 working days receipt of samples at the laboratory.

DNA testing methodologies

STR analysis - testing for full or half siblings

A brother to sister DNA sibling test analyses number of different DNA points (known as loci) in the persons tested. Full siblings and half siblings of course share a lot more DNA in common than do unrelated persons. Of course half siblings do not share as much as full siblings. The purpose of this test is therefore to look at the amount of genetic material shared and to apply statistical analysis to deduce the biological relationship.

Because the analysis is based on a comparison on common DNA, it is always best to submit the sample from any known parent/s of the person/s being tested. This will drastically help the evaluation process as it allows for a more accurate identification as we can then separate the maternal and paternal DNA of the individual being tested.

Visit the Interpreting the result of a DNA Relationship Test for more information on how to understand the result of your test.

For instructions on how to collect your samples visit our DNA sample collection guide. If you need to submit a sample other than an oral swab, we suggest that you visit our DNA forensic testing page for more information.

Contact us

To discuss further your siblings DNA test or any other relationship test you can contact us or, if you prefer, have us contact you directly.