Private paternity customers
Once we've received your samples at our laboratory we can start the testing process. You should expect to receive a report on your test results within 3-5 working days.

The report is accompanied by a covering letter which confirms our data protection policy - it states that:

Please note that unless you instruct us otherwise we will destroy the samples three months after the date of this report and any paper and computer records relating to the test will be destroyed after twelve months. It is important that you keep your copy of this report safe.

The wording of the actual report itself is designed to comply with the Family Law Reform Act 1969 which helps ensure that our DNA Paternity Test reports are accepted and widely used in court proceedings.

The report will either exclude a man from paternity or will provide conclusive evidence that he is the father of the child. If for example a child (Sarah Jones), her mother and her alleged father (John Smith) were tested, the report would be worded as follows:

In the case of a positive paternity result

Probability of paternity 99.9999%

Combined paternity index of 1,000,000 to 1

The putative father, John Smith is not excluded from the paternity of Sarah Jones. The results obtained are consistent with John Smith being the biological father of Sarah Jones and are one million times* more likely if John Smith is the father of Sarah Jones than if they are unrelated.

The probability of paternity given the DNA evidence is at least 99.9999% compared to an untested random man of the UK population.

*The actual figures quoted in the report will vary from case to case.

In the case of a negative paternity result

The DNA tests exclude paternity.

John Smith cannot be the father of Sarah Jones as he lacks the genetic markers that must have been inherited by the child from the biological father.

N.B. Please note the names used above are for example purposes only.

In addition to our contract for the Foreign and Commonwealth Office we also undertake relationship testing for private customers.

Private Immigration customers
In January 1991 a government scheme was introduced, which used DNA tests to resolve disputes in cases where it was not satisfied that persons seeking admission as children are related as claimed to their United Kingdom sponsor.

These relationship tests tend to be more complex than paternity cases and the process can take longer.

These test only apply to people's first application for settlement (or family reunion where the sponsor is a refugee but not where the sponsor has exceptional leave to remain).

Assessing DNA reports - advice from the Home Office

In assessing DNA reports, the question to be addressed is whether the evidence establishes the relevant relationships on a balance of probability:

If a DNA report concludes that the probability of a claimed relationship is at least three times greater than any other relationship, this should normally be accepted as proof of that relationship without further enquiry;

Where the DNA evidence concludes that the probability of the claimed relationship is only twice as likely (or less) than any other relationship, caseworkers should review the case as a whole. However, it must be remembered that even a low balance of probability in favour of the claimed relationship is substantial evidence and should be accepted unless there is strong evidence to the contrary.

The DNA report should be checked carefully to ensure that all of the children who are included in the appeal have been tested and are related as claimed to the alleged parents. Care should be taken to ensure that the persons tested (both children and parents) are the same as those included in the application or appeal. The fact that some children prove to be related as claimed does not constitute evidence in favour of other children who were not tested; refusal should be maintained in relation to any children not tested.

If you require further information Cellmark recommends that you look on the Home Office's website. Visa services manage the United Kingdom's entry clearance (visa) operation from visa offices in British overseas missions. Click this link to go direct to their website.