Home genetic tests meet primary care

Pop a plastic tube containing your saliva into the mail, and for $1,000 you'll get a detailed report of your genetic profile.

You and your patients are being invited to do this, thanks to new direct-to-consumer genetic testing companies, which enable clients to access results online. One such company, 23andMe, a privately held Web-based personal genome service, has been getting a lot of buzz.

Co-founded by biotech analyst and billionaire Anne Wojcicki, who is married to one of Google's founders, 23andMe (the name, of course, refers to the number of pairs of human chromosomes) has impressive credentials, as well as a very consumer-friendly and educational website. Though it's far from the first to offer DTC genetic testing, many earlier companies lacked credibility; some were merely shilling nutritional products. Thanks to the explosion in interest in consumer genetics that followed the Human Genome Project's completion in 2003, a cornucopia of personalized genetic testing enterprises are likely to follow.

People who nonetheless opt for genetic testing will need help evaluating results, understanding the difference between terms such as "presymptomatic" and "predisposed," weighing probabilities, and grasping the importance of environmental factors. Many of these people will bring their questions to the medical professional whom they trust-you.

Genetics create tough conversations

Those of you who've sent patients for genetic screening have probably already experienced the heart-wrenching dilemmas involved when, for example, patients learn they're likely to get Huntington's chorea or must consider pre-emptive breast or ovarian surgery because of the presence of genetic markers.

Now, with the proliferation of direct-to-consumer genetic testing, physicians who haven't talked with patients about genetic illness may need to think about how to handle these discussions. Some key aspects to consider: