Autosomal DNA is the DNA present on 22 of the 23 pairs of chromosomes of an individual. Each individual inherits half of their DNA from their mother and half from their father. Therefore by examining the DNA of a child and his alleged parents, it is possible to confirm if those individuals are his parents.

However while each child of the same parents will inherit 50% of their DNA from each parent, each child will not inherit exactly the same DNA as their sibling. Therefore, two full siblings are only expected to share approximately 50% of their DNA. It is possible to examine their DNA to determine if they are or are not likely to be related. This is called a kinship test.