About the X chromosome

The X-chromosome is found in both females and males. In every cell, females have 1 pair of XX chromosomes and males have 1 pair of XY chromosomes. The X chromosome contains far more genes than the Y chromosome. The X-chromosome carries about 2000 out of the 25000 or so genes, and the Y-chromosome about 78 (approximate figures). Females inherit an X-chromosome from the mother and an X-chromosome from the father. Thus, testing this chromosome is crucial when it come to determining relationships between females in DNA relationship testing. The genetic test involves mapping genetic profiles in X-Chromosome Testing.

 When would you do an X chromosome test?

  • The test is ideal if two or more females have different biological mothers and want to know if they share the same biological father.
  • In cases where two females share the same mother and want to confirm whether they share the same father. In this case, an X chromosome test can only be done if the mothers sample is included. We need the mother’s DNA sample in this specific case as it helps us establish whether the X chromosome profile we analyse was the chromosome inherited from the mother or from the father.
  • 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.

Real client testimonial:

The service was impeccable! I had an X chromosome test with a potential half sister, the test results came back over a week before they were due. The customer service is great too. I have used this company twice. Friends and family have too, we all share the same positive experience. Great company!” UK, 11th October 2016.

X chromosome testing requires a bit more time that other DNA tests. The cost of the X Chromosome test is $499, and the results for this test will be ready in 15 working days.

Note: We can only guarantee standard result turnaround time when testing takes place solely using oral swab samples. Using a discreet sample for your test may lead to an increase in turnaround time.