United States citizens can petition for their spouses, parents, children or siblings to immigrate to the United States and permanent residents can do so for their spouses and unmarried children.

DNA testing is required to confirm the relationship to the petitioner.

Ancestry
Exciting new advances in DNA testing now make it possible to trace all your ancestry with a single test.  Testing with the DNA  gives you an analysis of your entire ancestry, not just of one male or one female line.

Grandparentage Test

If the father is deceased or simply unavailable for testing, a grand
parentage test or an avuncular test can be performed.

A grand parentage test is often one of the better relationship tests to
perform to determine paternity of  a child.  The best testing scenario is a test which includes the mother, child and both of the alleged father’s parents (the child’s paternal grandmother and grandfather).  By including
both of the alleged father’s parents, the alleged father’s DNA profile can be reconstructed.  Comparing the alleged father’s reconstructed profile against the child’s DNA, can allow this testing scenario to give results as
accurate as a paternity test.

Siblingship Test
A siblingship test is useful for determining if individuals are full
brother/sisters, half brothers/sisters or unrelated.  Whenever the mother(s) is/are known, it is strongly recommended that they be included in the test. 
Including the mother(s) in the test can increase the results ten-fold, where you might see a probability of 98% instead of only 83%.

The fee for this test is based on the number of individuals tested.  Results are available 3-5 business days after receipt at the laboratory