Y-STR Paternal Ancestry DNA Test
The Y-STR (paternal ancestry) DNA test can confirm your relationship to long-lost relatives and paternal ancestors. This ancestry DNA test is also often used to provide additional
evidence in difficult paternity cases in which the alleged father
is not available for testing—indirectly, it can tell whether or not a child is related to the alleged father's brothers and other male relatives who share a common paternal line.
The genealogy DNA test is based on the fact that the Y chromosome is passed from father to son relatively
unchanged through many generations. The illustration to the right shows a typical inheritance pattern for the Y chromosome. Because the Y chromosome follows the same father-to-son pattern much like surnames in Western culture, the test has also been referred to as a "Surname Test."
Although the Y chromosome is only found in males, women can also indirectly participate in a Y-STR DNA test if they are interested in determining their paternal ancestry. They would need to ask a biological male relative, such as a father, brother, paternal uncle, or paternal grandfather to contribute a sample for comparison testing with her potential paternal relative or ancestor.
In a Y-STR DNA test, specific locations on the Y chromosome are examined to generate a Y-STR profile for each male tested. Males who are related through their fathers will tend to have the same or similar Y-STR profiles, and males who are not related will likely have different Y-STR profiles.
Most genealogy DNA testing companies allow for you to enter your DNA profile into a database with the hope of finding matches or possible relatives. At DDC, we provide the scientific confirmation of the relationship once you have identified a possible relative from your ancestry search—by performing a comparative analysis, testing both you and the possible relative using 17 Y-STR markers, which will tell you whether or not your Y-STR profiles are consistent, or not consistent, with the conclusion that you and the possible relative(s) may be related through a common male ancestor.
In a paternity situation where the alleged father is missing, Y-STR analysis cannot distinguish a specific relationship between
males who belong to the same paternal line. However, it is useful for excluding
males from an alleged biological relationship. For example, if a
male child and his alleged uncle (alleged father’s full brother)
are tested, their Y-STR profiles must match. If they do not, then
the alleged uncle is excluded (not considered a biological uncle)
and the alleged father is probably not the biological father.
There are many scenarios in which the Y-STR test may
be used. To determine if this test will help you in your particular
situation, please use our online contact form or call 1-800-453-6846.
One of our caring, knowledgeable case managers will review the information
you provide and guide you through the testing process. |
