Siblingship Test

  A siblingship test is a DNA test conducted to determine if two children share one or both parents (i.e., if they are half or full siblings). It is an indirect way to determine family relationships when an alleged father is not available for a paternity test. Results of a siblingship test may be used as proof in Social Security benefit and other inheritance claims.

A siblingship test starts with the analysis of known relatives:

  • Sibling 1 and Sibling 2 do not share the same mother and they want to find out if they share the same biological father—in this situation, a half siblingship test is performed.
  • Sibling 1 and Sibling 2 share the same biological mother but are unsure if they share the same biological father—in this situation, a full siblingship test is performed.

In the test, the siblings’ DNA profiles are compared to see how much of their DNA could have come from a common father. Participation of the mother(s) is encouraged to help exclude the mother’s contribution to the children’s DNA. Siblingship tests require more analysis, and they could be more costly and take a longer time to complete without the mother’s participation.

Sample Collection

  Samples for a DNA test are routinely collected using the painless and simple buccal swab, similar to a cotton-tipped swab. The swab is rubbed against the inside cheek of the test participant, and loose cheek cells adhere to the swab. Unlike regular cotton swabs, Pur-Wraps® provides a consistent surface for sample collection and DNA extraction.

Samples are collected using a chain of custody documentation process that ensures your results will be accepted by courts and other government agencies. Part of this process requires that a neutral third-party, such as a local laboratory or hospital, collect your samples. When you come to the sample collection appointment, you will be asked to do the following to meet the chain of custody requirements:

  • Present government-issued identification for the adults.
  • Present one of the following for minors: birth certificate or social security card.
  • Be photographed and fingerprinted.
  • Complete a Client Identification and Consent Form (the minor’s consent form should be signed by the legal guardian).