Y Chromosome Test (Y-STR)
Y chromosome testing (or Y-STR testing) is a reliable means of establishing whether alleged male relatives are really biologically related through the same paternal line. Cousins, uncles, nephews, siblings and so forth may all potentially be interested parties in a Y chromosome test.
All males carry a Y chromosome which is inherited from their father and is passed down from father to son.
What will my Y chromosome test result confirm?
Please note that your test results will not specify how the tested males are related. Meaning that the Y chromosome test will confirm whether or not the participants share the same paternal line, but will not specify the exact nature of relationship i.e whether two males are first cousins or uncle and nephew. The specifics of your case will then determine what the alleged relationship is or could be.
In the case of brothers wishing to know whether they have the same father, a Y chromosome test is the next best option if testing the father in a paternity DNA test is not a possibility.
You can request your Y chromosome test for just $589; this price includes the testing of two males with results ready in only 5-7 working days! If you want to proceed with the test simply click on the image below to order your test.
X Chromosome Testing between Sisters
We do offer this test Contact us to discuss alternative DNA tests.
Sisters may be unable to carry out a paternity DNA test if the father is deceased or unwilling/unable to be tested. An X chromosome test will in such cases allow you to establish whether you are:
- Half sisters or full sisters
- Half sisters or not sisters at all
It is important to note that we always advise doing a paternity DNA test where possible rather than the X chromosome test as the testing procedure for the X chromosome is more complex and thus, more expensive. Results for a paternity test are also more direct and conclusive.
X chromosome testing method explained
The X chromosome test is based on the fact that females receive one X chromosome from the mother and the other from the father. Therefore in the case where two sisters have different mothers, we can do an X chromosomes test without the need for the sample of the mother. The X chromosome test will therefore seek to establish whether they share the same X chromosome thus concluding they share the same father.
Two sisters that share the same mother and want to establish whether they are full siblings or half siblings will need to include their mother’s DNA sample alongside their own to be able to conclude the test. We will map the X chromosome pattern in the mother’s DNA sample and exclude this from the sisters’ DNA profile. We can then compare the remaining X chromosome pattern on the sisters’ DNA; if it matches it will indicate that they likely inherited their X chromosome from the same father. If the mother’s sample is not available then a siblings STR test is recommended.
Paternal grandmother and granddaughter
The X chromosome test can be used between paternal grandmother and granddaughter as they must share one X chromosome. This shared X chromosome is the one that the grandmother passed to her son and he, in turn, passed to his daughter. We only need DNA samples of the paternal grandmother and granddaughter for this test. We require no other samples in this particular case.
The cost of an X chromosome test for two sisters is N/A with you results ready within 15 working days. Proceed to order your test using the option below or if you have any questions you can request a call-back free of charge!