SISTER TO SISTER DNA TEST

There are two possibilities for DNA tests between sisters:

X-chromosome testing. Testing 2 or more sisters for the same father

This type of X-chromosome test is unique to DNA SOLUTIONS’ laboratories. DNA SOLUTIONS was the first company to offer DNA home testing kits, as well as paternity tests with superior accuracy. The company has now also introduced a testing method that allows a certain number of specific points to be tested on the X-chromosome.

• Accuracy of 99.9+%
• To establish whether or not two or more female persons with different mothers have the same biological father. The females being tested must have different mothers because, if 2 daughters with the same mother had an identical X chromosome, we would not know if this was passed down by the mother or father.
• Women have two X-chromosomes. Men only have one X-chromosome, which is always passed down to all their daughters. So a father and his daughters will all have one identical X-chromosome.
  
  Note: If two women with different mothers share the same X-chromosome, it does not guarantee they had the same father, as they could have had different fathers that were closely related. (i.e. their fathers could have been brothers, cousins, etc.).
• If you wish to know if 2 sisters also have the same mother, or you are not sure if they have different mothers, you will require a Full Sibling to Sibling Test.

Summary of X CHROMOSOME Testing Costs: £199 for 3 people (£99 for each additional person)

Full Sibling to Sibling DNA testing. Testing sisters as biological relations

• To establish whether or not two or more sisters have the same father or mother.
• Accuracy of 90+%
• You will require this test if:
  - the sisters to be tested have the same mother
  - the fathers of the sisters might be closely related
  - an X chromosome test is not applicable
• Uses DNA statistics to evaluate the amount of DNA sharing and to deduce a biological relationship. Full siblings have a lot more DNA in common than half siblings. Half siblings share more DNA than unrelated persons.
• For a higher accuracy, include DNA samples from parents or other siblings. This allows us to pinpoint the exact origin of each sibling’s DNA.

Summary of Full Siblingship Testing Costs: £299