OUR 99.99% GUARANTEE AND WHY IT IS SO IMPORTANT
There’s a big difference in small numbers, and this is why it’s important to find a lab that offers 99.99% probability of paternity. The different between a 99% and 99.99% probability, is that a result at 99.99% is 100 times more accurate.
HOW DOES THAT WORK?
For every DNA location tested, there is a number at the end of the column on a positive paternity report. This number represents how common that particular size of DNA is in the population group. For example, if the father were Thai, we use a Thai database that shows which DNA is common, and which is uncommon. All of these calculate into a Paternity Index (PI). The Paternity Index directly translates into a percentage. If you had an index of 99, you would take 99/100 = 99%; if it were 10,000,000 it would be 10,000,000/10,000,001, which would be 99.99999%.
WHAT DOES THAT ACTUALLY MEAN?
This means, that a DNA paternity test with a 99% probability of paternity has identified a DNA genetic pattern that, on average, 1 out of every 100 men would have. Thus, many people have this same pattern and would show the same result on the DNA paternity test.
At this level of reliability, a DNA paternity test could give the wrong result (a ‘false positive’) for 1 out of every 100 non-fathers in the population group (for example, Thai males) who are DNA tested.
A probability of paternity of 99.9% would, on average, identify the DNA genetic pattern of 1 in every 1,000 men. That’s still a considerable margin for potential ‘false positive’ results.
When you are trying to figure out who the father is of a child, a ‘1 in 100’ chance, or even a 1 in 1,000 chance, that a male could test positive as being the father even if they’re not, is not the best answer. And not what we consider a conclusive result.
Therefore, PTC Laboratories guarantees a minimum probability of paternity of 99.99% on every DNA normal paternity test (motherless tests, at-home tests and mutations are all included in our guarantee). At a 99.99% probability of paternity, on average, the identified DNA genetic pattern will fit no more than 1 in every 10,000 men in the population group. And most of our DNA paternity tests are even more discriminating than that, at 99.999+%.
The only exception to our 99.99% guarantee policy is when there is not enough genetic material to perform the test, which could happen when testing ‘unusual’ samples, such as cigarette butts, bed sheets, etc. In this instance, we will request a different sample to continue the test, in order to honour our 99.99% Policy.
Please note, that due to being such a new technology, Non-Invasive Prenatal Paternity tests via blood sample currently have a guarantee of 99.9%.
SO, HOW CAN SOME LABS OFFER ONLY 99%?
The industry-standard for relationship testing is AABB accreditation. Yet, even this accreditation only requires laboratories to DNA paternity test to a 99% probability of paternity. Companies can sell these kinds of tests because it is not yet illegal, and people buy them because they seem cheaper, and people believe the results because it is DNA evidence.
Often, labs that issue positive results of 99% probability of paternity will then offer to continue testing using a different method, such as RFLP, at an additional charge. At PTC Laboratories, our test fee includes testing, by whatever method necessary, to reach a 99.99% probability of paternity for all positive tests, including switching from PCR to RFLP testing, with no extra or hidden charge to you.