Can DNA be used to determine or deny a child's lineage, and what is the time limit for a father to perform li'an?

Summary

DNA testing is permitted under a court order in cases such as lineage disputes, unknown parentage, hospital baby mix-ups, test-tube babies and children missing in disasters. DNA may not be used to deny a child's lineage or to take the place of li'an, because it is only supporting evidence and not primary proof. Denial through li'an must be made promptly, from the time the wife's pregnancy is confirmed until three days after birth, with delay allowed only for a valid excuse. A denial made after this period is rejected and the child is established as the father's.

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