DNA Relationship tests determine the statistical probability of whether:
- Brothers/sisters share the same father, mother or even two parents or not;
- Likelihood of relatedness between a child and one or both grandparents;
- Likelihood of relatedness between a child and an aunt or uncle;
The cost of the DNA testing service includes two individuals, you may add more as needed; for instance a third sibling at an additional cost. Please select this option in the drop down menu located on the order page.
When the issue of siblingship is in question, the recommended method to determine whether individuals are true biological siblings is to test their parents. In situations where the alleged parents are unavailable for testing, a DNA siblings test can be performed to analyze the relationship of biological siblings.
Including one common parent greatly increases the accuracy of this type of analysis and is recommended if at all possible. If this is not possible, disclosing that siblings share a common mother or father can also lead to more meaningful results.
Unlike a paternity test which will always provide a conclusive result, siblingship tests are different. When a siblingship test is conducted, the DNA laboratory will determine the genetic profile of the alleged siblings. Based on the type of genetic material inherited by each sibling, a siblingship DNA index is determined. If the siblingship DNA index is less than 1.00, this indicates non-relatedness. If the siblingship DNA index is greater than 1.00, this indicates that the two tested individuals are more likely to be true biological siblings. The higher the value of the siblingship DNA index, the greater the likelihood that the two individuals are true biological siblings. To analyze the possibility that the siblings share only one common parent versus two common parents (mother and father), a half siblingship DNA index is obtained. The ratio of the half siblingship DNA index versus the full siblingship DNA index would provide you with an idea of whether the two individuals are more likely to share only one common parent (e.g. mother only) or two common parents (mother and alleged father).
Our siblingship tests are preformed using what's known as an "All-vs-All" methodology. For example, if you have two siblings, Alice and Bob, one report will be generated which details the relationship between Alice and Bob. With three siblings you would receive 3 reports which describe the relationships between: Alice & Bob, Alice & Charlie, Bob & Charlie. Four siblings would yield 6 reports and so on. The amount of reports would subsequently grow exponentially. If you have any questions regarding these reports, please feel free to contact us.
Please note: In some cases, a Y-STR DNA Test can provide more conclusive results for males determining common paternal lineage. If siblings are trying to determine whether or not they share the same maternal lineage, an X-SV DNA Test may be the analysis of choice.
Don't wory, we will choose the best testing method to get most accurate results!
A Grandparent DNA test calculates the likelihood of relatedness between a child and one or both grandparents.
A child inherits exactly 50% of its genes from its biological mother and 50% from its biological father, that child shares exactly 25% of its genes with each biological grandparent. If both biological parents of the alleged parent are tested and they do not possess the paternal or maternal genes between them, then they are excluded ruled out as the biological grandparents. When both biological parents of the alleged parent possess the paternal or maternal genes between them, they are not excluded as the biological grandparents.
It may not be possible to obtain conclusive results in a grandparent DNA test if both alleged grandparents are not tested. We recommend testing both alleged grandparents as well as one parent if possible to achieve the most accurate results, similarly to the Missing Parent DNA test.
It is also important to understand that, in reporting the results of a DNA grandparent test, the laboratory assumes that the tested alleged grandparents are, in fact, the biological parents of the unavailable, alleged parent. If there is any question regarding the paternity of the unavailable alleged parent, then the alleged biological grandfather should not be tested.
All grandparentage tests utilize stringent, validated testing procedures and include up to 22 STR loci plus the gender identification marker amelogenin in order to achieve 100% accurate results.
Avuncular tests calculate the likelihood of relatedness between a child and an aunt or uncle.
A child inherits exactly half of their genes from their biological father and the biological father shares around half of his genes in common with his full sibling, therefore the child will share around half of its paternal genes in common with the full sibling of the biological father. Based upon the number of genetic matches, the laboratory calculates the statistical likelihood that the alleged aunt/uncle is biologically related to the child versus being unrelated.
It may not be possible to achieve a conclusive result. Even though the siblings may have the same biological parents, the alleged father is not genetically identical to the alleged sibling and have different genetic markers. On the average, testing an alleged father’s full sibling allows us to determine only half of his genes.
To increase the certainty of the results, testing the mother of the child is strongly recommended, as this allows us to identify genetic markers of the child that were inherited maternally and to eliminate them from consideration as possible paternal markers.
All avuncular tests utilize stringent, validated testing procedures and include up to 22 STR loci plus the gender identification marker amelogenin in order to achieve 100% accurate results.
How to take samples:
