more frequently asked questions

What DNA samples are used for paternity or maternity testing?
A sample is taken from inside the mouth of the child and both parents. Contrary to popular belief, what is required is not saliva, but actual skin cells from the cheek which rub off easily and painlessly using a specially designed ‘buccal swab’ (cotton bud).

Can a second man be tested later without re-swabbing the child?
Unfortunately, no. Unless the first test was Court Approved, a complete new test must be done.

Will you tell my doctor or the CSA about my test?

Absolutely not! We are a private clinic, and are not linked to the NHS or any government agency. We respect your privacy.

I want to secretly test someone’s DNA without them knowing. Can you help?
No. Having human tissue with the intention of its DNA being analysed, without the consent of the person from whom the tissue came, is unlawful under the Human Tissue Act.

Why do you ask for the mother’s DNA in a paternity test?
It is important that both parents’ DNA is sampled to determine which genes in the child were inherited from the mother. The remaining genes must have been passed down by the child's biological father (paternal genes). The tests can then focus on just these genes.
It is still possible to conduct the test without the mother’s DNA, but we do normally require her written consent in any case. A motherless paternity test reduces the accuracy of the test and in very rare cases, produces inconclusive results.

What happens if a conclusive result cannot be obtained?
Sibling and Grandparentage analysis is never as conclusive as parentage analysis. A typical result might be 0 - 5% probability of a relationship (strong evidence that a relationship does not exist) or 85 - 99% (strong evidence that it does). However, there is a possibility with Sibling and Grandparentage tests that a result in the 30 - 70% range is obtained – which is inconclusive. More information >

In rare cases where the outcome does not produce strong evidence one way or another, you can opt for an extended study in which the DNA from the original mouth swabs is subjected to additional analysis. There is a further fee payable.

Can twins have different fathers?
Yes. If a woman has sex with two men at short intervals within the same ovulatory period, so-called ‘heteropaternal superfecundation’ may occur.

Why do you need to know my ethnic group?
In order to calculate the probability of a relationship, it is important that we know the probability of genetic markers matching just by chance. A ‘positive’ test result will be expressed something like this:

“It is 19.9 billion times more likely that the alleged father is the biological father of the child than an unrelated man of similar ethnic origin.”

Different ethnic groups have different random match probabilities.

< back

even more >