Could next election season's dirty tricks include disclosures about the candidates' genes?

This year we heard all about John McCain's battles with skin cancer and Barack Obama's smoking habit, but there were gaps in their health records. It was unclear whether McCain — at 72 he would have been the oldest president elected to a first term — had been screened for memory deficits, or whether Obama had stopped smoking. Now, the proliferation of genome profiling products suggests that candidates' DNA could be fair game for public consumption, according to a commentary in today's New England Journal of Medicine.

In scenarios resonant of CSI and Law & Order, sneaky politicos could run DNA tests on hair follicles shed by their unwitting opponents or on their used coffee cups or cutlery, write Boston University's George Annas, a bioethicist, and Robert Green, a neurologist.

While genome scans can pick up some associations with disease, including DNA links to coronary artery disease and prostate cancer, they aren’t usually predictive, Annas and Green write. Moreover, they say, the tests are likely to turn up false positive results and findings with "dubious" meaning.

"We think future presidential candidates should resist calls to disclose their own genetic information," they write. "We recommend that they also pledge that their campaigns will not attempt to obtain or release genomic information about their opponents."

How would those policies sit with a voracious media, which has been reporting on presidential candidates' health since 1972 when George McGovern replaced his running mate Thomas Eagleton after word leaked that his veep pick had been hospitalized for depression? And would the electorate protest? President Bush this year signed legislation safeguarding genetic privacy into law, but celebrities, including Google founder Sergey Brin, and a consortium of science leaders in recent weeks made their own genetic codes known.

Image of DNA by iStockphoto/Luis M. Molina