All About DNA Testing Accuracy
Why will results claiming probable inclusion never equal 100%?
In paternity testing, no man will ever be 100% included as the biological father because there is always the slight possibility that the DNA profile of the alleged father matches the DNA profile of the child by mere chance. The likelihood of this happening is usually well below 0.001% (1 in 100,000), but it depends in large part on the ethnic origin of the individuals involved. In addition, it important to note that the certainty usually increases with the number of DNA loci (locations) analyzed. Look for a company that routinely checks at least 15 different loci and that will run additional tests on more locations if there are mutations or inconsistencies.
What does 99.99% probability really mean?
For paternity cases, if the alleged father is not the biological father, the result will be 100% exclusion. However, if the alleged father cannot be excluded as the biological father, the result will be a certain percent inclusion. Make sure you look for a lab that routinely provides at least 99.99% probability of inclusion. This means that there is only a 0.01% chance that another random individual in the same race population could have the same paternity test results. Consider that many companies provide 99.9999% probabilities of inclusion, meaning there is only a 0.0001% chance that another man could be the father.
You should pay close attention to how DNA testing companies describe their testing and results. Even if the test concludes that the alleged father is 100% excluded as the biological father, the test may not have been 100% accurate. False exclusions can occur if a laboratory mixes up the test samples, and the results are for individuals from more than one case.
False inclusions can also occur. If the result is 99.0% inclusion, the chance of a false inclusion is 100 times greater than a 99.99% inclusion.
|Click on the logos below to visit DNA company websites.