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Sibling ship DNA Test

A Siblingship DNA Test determines the biological relationship between siblings. Comparison of the DNA of two individuals can provide information about whether they are full siblings, half siblings, or not related

I want to know if I and my sibling share the same mother and/or father. Will a Sibling ship DNA Test help me?

Ideally, the best method to determine whether individuals are true biological siblings is to test the parents. DNA paternity and maternity testing will always provide conclusive results. However, sometimes the alleged parents are unavailable for testing. In this case a Siblingship DNA test determine the relationship of biological siblings. The results of the test are accurate and can provide peace of mind.

What Are The Types Of Siblingship DNA Tests?

Two types of siblingship DNA tests are available:

How the Siblingship DNA Test Works

The DNA laboratory extracts the genetic profiles of the alleged siblings and creates a siblingship index.

If the siblingship index is less than 1.00, this indicates non-relatedness. If the siblingship index is greater than 1.00, then the two tested individuals are more likely to be biological siblings. The higher the value of the siblingship index, the greater the likelihood that the two individuals are biological siblings.

Half Siblingship

To analyze the possibility that the siblings share only one common parent versus two common parents (mother and father), a half siblingship index is obtained. The ratio of the half siblingship index versus the full siblingship index will indicate whether the two individuals are more likely to share only one common parent or two common parents (mother and alleged father).

A siblingship DNA test will provide you with an indication of whether you are more likely to be a full sibling, half sibling or not the true biological sibling of the other tested individual.

Though biological brothers share similar DNA markers, some additional information is needed in such cases. A paternity DNA test is a better choice.

Siblingship DNA Test is based on the following facts:

  • Every child inherits half of his genes from each parent. For full brothers and full sisters the genes would be a 50% match.
  • For half-brothers and half-sisters, i.e. for siblings who have either the biological mother or father in common, the genes would be a 25% match.

Oral swab samples are the most common  for conducting a siblingship DNA test. If possible we suggest that the biological mother’s DNA sample also be submitted to increase the odds of a conclusive result. .

Yes.  If all  siblings are males, the Y chromosome test will provide you the answers. All males in the same family share the smnaem Y chromosome.

  • If siblings were separated during childhood or at birth
  • To verify the biological father of yours and your siblings if father is not available
  • To understand if you are full or half siblings 
  • In cases where maternity DNA test and paternity DNA test are not feasible.
  • To settle inheritance claims or property disputes as per law.

Please understand that any DNA test needs the consent of the individuals whose DNA samples are being tested. For a siblingship DNA testing, it is suggested that the mother’s DNA samples are also submitted.

If the individuals to be tested live in different cities, or even different countries, each specimen can be collected individually and compared once the lab has them.  Please let us know this when ordering.