DNA paternity testing is showing up everywhere now, but it’s possible to use DNA testing to determine more than just paternal or maternal relationships. It’s also possible to determine sibling relationships. DNA siblingship tests can be used to find out brothers and sisters share the same two parents or not. A DNA siblingship test is most useful when the alleged parents are not available for DNA testing, although the accuracy will be greater if a leas one parent can be included in the DNA relationship testing.
DNA siblingship tests do not always provide conclusive results. Genetic profiles are determined for each of the alleged siblings. From these profiles, a siblingship DNA index is computed. If it’s less than one, then the patients are not related. Indices greater than one suggests that relationship is more likely. The higher the value of the index, the higher the probability of sibling relationship. DNA relationship testing is also available to determine relationships between aunts and uncles with nieces or nephews.
One interesting arena in which DNA relationship testing is becoming more common is immigration. In the past, paper documents like birth certificates or medical records were required to prove familial relationship. But many times these aren’t available, especially in situations where individuals have fled their home country to escape war or persecution. The use of photos to prove relationship is unreliable. DNA testing for relationships is reliable to the point of statistical certainty and its use in immigration cases is becoming much more common.
In countries like the U.S., where relationship to citizens or permanent residents can be used as a basis for immigration, genetic testing is becoming the norm. DNA relationship testing is done in the same way as DNA paternity testing. DNA samples obtained by swabbing patients’ cheeks are compared to determine whether a relationship exists.
DNA relationship testing has been particularly useful for immigrants from parts of Asia and Africa. These regions are often plagued by fraud or political upheaval. With public records in such a chaotic state, DNA relationship testing provides the necessary
One DNA lab reports that DNA relationship testing for immigration has increased from eight per month to about 40 per month in just five years. DNA relationship testing is done voluntarily and often as a last resort. But it provides strong proof and can increase the processing time by a factor of ten or more. Green card processing can often take thousands of dollars, so an extra couple of hundred dollars for a DNA relationship test is well worth it.