A sample of cells is taken from the alleged father, the mother and the child. A laboratory provides the testing. The tests compare many different and complex details of the child's cells with similar details in the mother's and alleged father's cells. The tests can show the man is not the father of the child. The tests also show the man probably is the father.
Genetic testing is very accurate.
A court decides who pays for genetic testing. A court usually orders the alleged father to pay the costs. A person of any age can be tested. The age of the father or mother is not relevant under Nevada paternity establishment laws. Nevada law permits paternity action to be started anytime before the child reaches the age of 21.