• Understanding the Paternity Test result

    Posted on September 30, 2013 by in Uncategorized

     A paternity test result is a scientific report; there will be a number of key terms that you should know in order to fully comprehend the result when you receive it. In this article we will discuss a number of terms related to the results as well as some important issues regarding how long do the results of a paternity test take to be released. Important to note that the results of a peace of mind test and a legal paternity test will be the same. It is the way in which samples are collected that differs between the two.

    How accurate are Paternity Test Results ?

    To understand how accurate the paternity test results are we need to look at the Probability of Paternity; this term, sometimes abbreviated as POP will be stated on your DNA test report. The POP shows the percentage probability that the alleged father is the biological father of the child. If the alleged father is the biological father of the child, the paternity test result will show a Probability of Paternity that will be in excess of 99.99%. If the alleged father is not the biological father of the child, the paternity testing result will show a Probability of Paternity of 0%. Inclusion of the mother’s sample is usually recommended in a paternity test as it will help give more accurate DNA test results. Having the mother’s sample will help scientists determine the alleles (refer to alleles further down in this article) inherited by the child from the mother. However, in the majority of cases, people opt to do a motherless paternity test. The prenatal paternity test is an exception as the mother’s DNA profile is always included in the test if the test is done using amniocentesis or CVS.

    More scientific articles and information can be found by visiting  World Science.

    How long do Paternity Test Results take ?

    The turnaround time can vary from one company to the next. Some companies offer very short turnaround times, providing results in 3-5 working days, other companies may take longer. Most companies will offer express DNA testing which makes it possible to have your results in 2 working days. How long do paternity test results take will also depends on the type of test you are doing; paternity testing results might take X number of days to be ready but other DNA tests might take longer as the laboratory testing procedure might require more time. One further issue to keep in mind: you must begin counting the turnaround time from the day your samples are received in the lab and registered into the system.

    Although one is clearly anxious to receive the result of their paternity test, it is important to know that a laboratory has its own processes and therefore the client must wait for the stated time to elapse before chasing the result not before.

    What does a Paternity Test Result look like ?

    There is no fixed template/format for DNA test results as different laboratories might use different templates/formats. Some companies will issue results which span over several pages whilst other will keep it to a single page. For paternity test results, the result will state any of the following clearly (although the wording may vary slightly) .

    • “The alleged tested father, A B, cannot be excluded as the biological father of the child, X Y, as they share genetic markers” (this means that the alleged father is the biological father of the child);
    • “the alleged tested father, A B, is excluded as the biological father of child, XY, as they do not share the same genetic markers” (this means that the tested father is not the biological father of the child);

    Some important terms in your Paternity Test Results

    Allele: A gene can have more than one form. An allele refers to one of these forms. It is, in simple words, an alternative form of a gene.

    Genetic markers: We inherit half of our genetic material from our father and another half from our mother. In a paternity test, DNA analysts extract a DNA profile showing a number of genetic markers (or genetic loci) found on the DNA of the alleged father and child. Each genetic marker has two alleles; one allele inherited from the mother and one inherited from the father. Let’s assume we have carried out a paternity DNA test with the mother’s sample. One of the genetic markers on the child’s locus displays the two alleles 10 and 12. The mother’s DNA profile for that particular genetic marker displays alleles 12 and 8. We can conclude that the 12 allele was inherited from the mother and the 10 allele was inherited from the child’s biological father. If the tested alleged father displays more than two alleles which do not correspond to the alleles of the child, it means that the man is not the child’s biological father.

    There may in some cases be a mutation on a gene which might result in one mismatched allele between the profile of father and child – this might happen in cases where the mother’s sample has not been included; in this case, the mother’s sample will be definitely required to provide a conclusive result. All the genetic markers tested will be displayed in a table and you can easily work out which alleles match and which alleles do not.

    Paternity Index: The probability that a genetic marker was passed on to the child from the alleged biological father rather than from another unrelated man in a population. Laboratories have a database which lists the distribution and frequency of alleles in a population and use this to work out the paternity index.

    Combined Paternity Index: For each of the loci (genetic markers) tested, scientists take the Paternity Index for each one of these and multiply them all together (if for example, 15 loci are tested, there will be a multiplication of all 15 paternity indices). This multiplication is referred to as the Combined Paternity Index. The Combined paternity index or CPI shows how many times more likely it is that the test alleged father is the biological father of the child when compared to another random man of the same ethnic background.

    Your paternity testing will be a determining factor in the choices you make. Should you have any problems, the DNA testing company of your choice will definitely clarify any queries about your paternity test result.