As you study DNA, you find that every person's DNA is different from another's. Identical twins are the only people whose DNA is the same. Consider your parents and your siblings. Even though your brother and your sister have the same parents, it is unlikely that you look exactly like them unless you are identical twins. You may have common features, and you will all share common DNA among yourselves, but only identical twins will have the exact same DNA. DNA testing is used for many reasons such as the following:
- Identify potential suspects whose DNA may match evidence left at crime scenes
- Exonerate persons wrongly accused
- Match organ donors