Given the availability of many genetic tests to anyone willing to pay for them, however, clinicians are soon likely to face anxious patients equipped with genotype information showing them to be at risk for multiple diseases. This may provide a “teachable” moment for encour-aging patients to apply known preventive strategies against the conditions for which they are at increased risk. Such encounters also provide critical opportunities to discourage complacency in preventive strategies for which geno-typing information suggests a patient is not at increased risk. This is because so little is known about genetic influences on complex diseases and because variants identified to date typically explain so small a proportion of population risk. It may be useful to point out to patients considering purchasing these tests that obtaining a family history is often simpler and almost always cheaper. A positive family history typically confers a three- to fourfold increase in the risk of many diseases and is extremely useful in identifying persons to target for more intensive screening (61).
