A genetic test determines the DNA sequence of a certain region of the human genome. This region could be a whole gene, a portion of a gene, or other areas thought to regulate genes. The test will look for certain changes in the sequence that are known to have consequences on the function of a gene. These tests can be used to: 

  1. diagnose a disease or other trait,
  2. determine if a person is a carrier of a mutation that could lead to disease in their children, and
  3. predict if a disease or trait that is not yet detectable by other medical tests may occur in the future.