Welcome to DNA Tests Direct Canada! Your DNA holds a wealth of information, and understanding your test results is the key to unlocking those insights. Whether you’re exploring family relationships, ancestry, health predispositions, or personal traits, your report is unique to you.
The Science Behind Your Results: A Quick Look
Our DNA tests use advanced methods to analyze your genetic makeup. Here’s a brief overview of what we look for:
- For Relationship Testing (e.g., Paternity, Sibling): We primarily analyze Short Tandem Repeats (STRs). These are regions of DNA where short sequences of genetic code are repeated. By comparing the STR profiles of individuals (we analyze up to 27 STR markers), we can determine biological relationships.
- For Other Tests (e.g., Traits, Health, Ancestry): Many of these tests detect DNA changes known as Single Nucleotide Polymorphisms (SNPs) – pronounced “snips.” These occur when a single DNA building block (a nucleotide) is different from the usual. Thousands of SNPs are linked to various attributes, from disease risk and athletic ability to how you might respond to certain foods.
- We can also detect other changes like Variable Number Tandem Repeats (VNTRs), which are similar to STRs but with larger repeated regions, and large deletions or insertions, where sections of DNA might be missing or added. The impact of these changes depends on where they occur in your genome.
Now, let’s find the specific information for your test.
Relationship DNA Test Results
Our relationship DNA tests analyze up to 27 STR markers to establish biological connections. The interpretation varies slightly:
DNA Paternity Tests
Your test will show a probability of paternity (greater than 99.99999% for inclusions) or confirm an exclusion (100%). The results will clearly indicate whether the tested man is the biological father of the child.
DNA Twin Test (Zygosity)
This test is definitive. Identical twins will have the exact same STR profile. Fraternal twins will have profiles similar to siblings, sharing approximately 50% of their DNA.
DNA Sibling, Grandparent, Aunt/Uncle, Cousin Tests
Statistical analysis for these relationships is more complex because the amount of shared DNA decreases as individuals are more distantly related. We determine an “index value” as a strong indicator of whether a biological relationship exists.
Results typically indicate the likelihood or statistical probability of the tested biological relationship.
Important Note for Relationship Tests: Wherever possible, testing a direct parent-child biological relationship allows us to provide the most conclusive results.
Other relationship tests
Each of our relationship tests are conducted just the same as the paternity test. We analyze up to 27 STR markers from each of the individuals being tested, to determine if there is a match.
- For Maternity Testing, half of a child’s STR profile will be an exact match to half of their mother’s STR profile (just like for a child-father relationship).
- For Twin Testing: Identical twins will have the exact same STR profile, while fraternal twins will be more like a sibling relationship profile and only share approximately 50% of their DNA in common.
- Statistical analysis involved in the other relationships are more complex. This is because the further apart two individuals are biologically, the less DNA they have in common. In these circumstances, we will determine an “index value” that is a good indicator of whether or not a biological relationship exists between two individuals.
- Remember, wherever possible, it is best to test for a parent-child biological relationship, as this enables us to provide completely conclusive results.
Our other tests
Many of our other tests detect other DNA changes known as single nucleotide polymorphisms or SNPs (pronounced “snips”). These occur when just one of the DNA building blocks (nucleotides) has been changed to something different. SNPs occur throughout the genome. Thousands of SNPs are linked to different attributes, from disease risk, to hair color, athletic ability, and food response. Some SNPs are detrimental to human health, others can provide an advantage, while others just contribute to differences in our appearance.
Other DNA changes that we can detect include VNTRs and large deletions or insertions. VNTRs (variable number tandem repeats) are similar to STRs (described above in the paternity testing), but the repeated region is larger. Larger deletions or insertions can occur when large sections of DNA are “missing” or “added” to a person’s genome. The affect of these bigger changes depends where in the genome the change has occurred.
