Exactly how accurate are DNA tests, and how much can your genetic data really reveal about you? To find out, we asked a molecular biologist.

With genetic testing for health, ancestry, paternity and more becoming increasingly popular, many people are left wondering: exactly how accurate are DNA tests? Whether you are taking a DNA test to build your extended DNA family tree with an AncestryDNA(opens in new tab) testing kit, or want precise information on hereditary health conditions with 23andM...