New Study: DNA Tests For Healthy People Have “Uncertain Value”

did not seem to produce more anxiety or depression, but more people in that group reported changing their diet or exercise.

Medical providers and insurers are wary of “a wave of unnecessary diagnoses and treatments. We’ve gone through this problem with PSA in the past,” says cancer geneticist Edison Liu, president and CEO of the Jackson Laboratory in Bar Harbor, ME. PSA refers to the prostate-specific antigen screening test, once de rigueur for older men. It was later found to do more potential harm than good and is no longer a routine procedure.

The appropriate frequency of mammography to screen for breast cancer is a matter of debate among different medical organizations and even the U.S. Congress. The risk of unnecessary tests, scans, and surgeries has also colored the current pursuit of a blood test that can screen for early signs of cancer.

With genetic tests, a big problem is knowing whether an abnormality that pops up is a mutation linked to a disease or is a benign variant. “To call a mutation a mutation is a challenge,” says Liu. (His organization is not associated with the MedSeq study, but it is studying the value of tumor DNA testing for community oncologists in Maine who don’t have access to the resources of elite medical centers.)

Vassy says that the field is moving forward because variant databases are linking up, deepening the pool and the understanding of each variant’s disease risk. But perhaps more important, says Vassy, is better interpretation of variants. “It’s still a fairly expert, manual process,” he says. “Those high quality interpretations need to be shared.”

MedSeq will continue to follow the first 100 participants up to five years, says Vassy. The study also aims to be more diverse and is now recruiting a new cohort of African-American participants.

Author: Alex Lash

I've spent nearly all my working life as a journalist. I covered the rise and fall of the dot-com era in the second half of the 1990s, then switched to life sciences in the new millennium. I've written about the strategy, financing and scientific breakthroughs of biotech for The Deal, Elsevier's Start-Up, In Vivo and The Pink Sheet, and Xconomy.