Can a DNA test determine siblings?

Can a DNA test determine siblings?

Can a DNA test determine siblings?

A DNA test can determine siblings. In fact, it is the most scientific and accurate way to prove that two or more individuals are biologically related.

A sibling DNA test can establish whether brothers and sisters share the same mother and father, or share either the mother or the father. Full siblings are brothers and/or sisters that have the same biological parents. Half-siblings share only one biological parent, either the mother or father.

In AlphaBiolabs’ Sibling DNA test the two alleged siblings need to provide a DNA sample. This is a simple process and only involves rubbing a mouth swab on the inside of a mouth to collect cheek cells. When these swabs are returned to our in-house laboratory, the DNA is extracted from the cells. Our DNA experts then use statistical analysis to evaluate the amount of DNA shared between the individuals tested. Full siblings will have more DNA in common than half-siblings, and half-siblings normally share more DNA than unrelated individuals.

Guaranteed DNA results or your money back

AlphaBiolabs is a UKAS-accredited testing laboratory (No. 2773), to the quality technical standard of ISO 17025, and we are certified to ISO 9001. We also employ some of Europe’s leading DNA scientists to ensure the highest level of technical ability. This ensures that your DNA tests are accurate and performed to the highest standards.

Our paternity DNA tests always provides a conclusive result. This is because it is possible to identify which half of the child’s DNA is inherited from the father and which half is from the mother. If the man undergoing DNA testing is the biological father, both child and father will share identical sections of DNA at each marker analysed. If the tested man is not the biological father there will be differences in the DNA.

Sibling DNA tests are more complex to analyse, which means that you may not get a decisive answer. Across the testing industry, sibling DNA testing can be up to 40% inconclusive. In other words, four out of every 10 people will not get the result they have paid for. AlphaBiolabs has been able to reduce the inconclusive rate down to 24%. However, should you use our sibling DNA testing service and not get a conclusive result, we guarantee to refund the price of your sibling test.

Our sibling DNA test can be ordered online today for just £149 with guaranteed results or your money back. Results are available the next day, or you can upgrade to same day results for an extra £70.  

Further details on AlphaBiolabs’ sibling testing and other DNA testing services can be found on our website. Alternatively, please call our Customer Services team on 0333 600 1300 or email