The test would likely cost several hundred dollars--a cost that, in terms of potential preventative benefits, might be well worth it. And it's a first step toward what might eventually become a kind of cancer screening carried out by saliva swab. In the meantime, the researchers hope the tool might be used to help influence patients' lifestyle choice. For instance, smokers could be shown exactly how their habit is damaging their DNA via high counts of DNA adducts. Future tests could then show, in plain terms, how curbing a behavior like smoking can have a direct impact on one's genetic health.