How do I read my DNA Paternity Test results report?

Your DNA Paternity Test Report contains scientific terms that are required for regulatory and legal reasons. This guide will help you understand the different sections of your report.

What's In Your Report: An Overview

Your DNA Paternity Test Report will consist of the following 3 pages:

• Page 1 (Cover Page): Shows your Case Number (also your Order ID) and the first names of everyone tested.
• Page 2 (Results Page): This page displays the main results of your DNA Paternity Test. It includes a chart showing the genetic markers (DNA profile) for each person tested.
• Page 3 (Information Page): Contains a glossary of terms used in the report and guidelines for interpreting the results.

The Science Behind the Test

DNA paternity testing examines specific genetic markers (Short Tandem Repeats or "STRs") at known locations ("loci") in your DNA. At each locus, you have two genetic variants ("alleles") - one inherited from your mother and one from your father.

The laboratory uses a technique called polymerase chain reaction (PCR) to analyze these markers. In a true biological parent-child relationship, at least one allele at each DNA locus in the child's DNA profile should match with the biological parent's DNA.

Understanding the Results Chart

On page 2 of your report, you'll find a chart with the DNA profiles. It might look something like this:

Here's what the columns mean:

• DNA Locus: This column lists the names of the genetic markers analyzed in your test (e.g., D8S1179).
• Child/Alleged Father: These columns show the two alleles found for each person at that specific DNA locus.

  • If two different allele numbers are listed (e.g., "13, 14" for the child at D8S1179), it means the person inherited a different allele version from each parent.

  • If only a single number is listed (e.g., "13" for the alleged father at D8S1179), it means the person has two identical copies of that allele, having inherited the same version from both parents.

• Paternity Index (PI): This number shows the statistical strength of a match at that specific DNA locus. The PI considers how common or rare an allele is in the general population. A higher PI suggests a stronger match.

A "match" occurs if the child and the alleged father share a common allele number at a specific locus. In the example above, at D8S1179, the child has alleles "13" and "14" while the alleged father has two identical copies of allele "13" (shown simply as "13"). Since the "13" allele appears in both profiles, the alleged father and child match at this locus.

If there is no match between the alleged father and child at a particular locus, the Paternity Index will be 0, as shown below:

Combined Paternity Index (CPI)

After analyzing all the DNA loci, the individual Paternity Index (PI) values are multiplied together to calculate the Combined Paternity Index (CPI). The CPI value is a measure of the overall strength of the genetic evidence from all markers tested. It tells you how many times more likely it is that the tested alleged father is the true biological father compared to an unrelated, randomly chosen man from the same population.

Probability of Paternity

This is the final result of the paternity test and is calculated from the Combined Paternity Index (CPI). It states the likelihood that the alleged father is the biological father.

• A CPI value of 0 corresponds to a probability of paternity of 0%
• A CPI value greater than 1000 corresponds to a probability of paternity greater than 99.99%

Test Outcomes

In a DNA Paternity Test, your test report will indicate one of two possible outcomes:

If the alleged father IS NOT the true biological father, your report is expected to state:

PROBABILITY OF PATERNITY: 0

If the alleged father IS the true biological father, your report is expected to state:

PROBABILITY OF PATERNITY: >99.99%

We hope this guide helps you understand your DNA Paternity Test results. If you have any further questions, please don't hesitate to contact us.