Drug store health testing is about to take a big step beyond pregnancy tests. San Diego based startup Pathway Genomics announced today that it will begin selling its DNA collection kits at Walgreens drugstores beginning in mid-May, for about $20 to $30. Unlike a pregnancy test, users won’t be able to get results immediately. They will have to send in their saliva sample and then go to Pathway’s website to select the particular test they want. Users choose from drug response ($79), which assesses how well an individual can metabolize certain drugs, predicting the best dosage for that person or whether they will be susceptible to certain side effects; pre-pregnancy planning ($179), which determines whether parents carry mutations for serious genetic diseases; health conditions ($179), which assesses risk for a number of conditions, including diabetes, Alzheimer’s, prostate cancer and more; or a combination of all three ($249). The kits won’t be sold in New York because the state’s laws require medical professionals to be involved in this type of testing.

Pathway’s competitors in the consumer genomics market include 23andMe, Navigenics, and DecodeMe, three companies that pioneered direct-to-consumer testing through the internet, as well as the more recent contender, Counsyl, which specializes in carrier testing. The latter allows prospective parents to determine their risk for passing more than 100 different genetic diseases on to their child. It’s not yet clear how Pathway’s tests will stack up against the others, though they certainly do seem cheaper. (Counsyl’s test costs about $400, but is covered by some major insurers. 23andMe’s genome wide test sells for $400 to $500, while Navigenics’s sells for about $1000. I don’t have enough information on Pathway’s tests to determine if they assess as many genetic variants as the more expensive options.)

Pathway seems to be following a trend in consumer genetic testing–rather than taking a broad snapshot of the genome, it is offering specific targeted tests, such as the pre-pregnancy and drug response tests. Broader tests that predict risk for specific diseases, such as Parkinson’s, have been controversial because it’s not yet clear how useful this information is in making medical decisions. Drug response and pre-pregnancy or carrier testing are widely considered to be the most useful and actionable of the various types of medical genetic testing now available. People can use pharmacogenomics information to guide later prescribing decisions, and carrier information to choose whether to screen embryos for specific genetics diseases. Navigenics is also offering pharmacogenomics test, though it appears to be part of their larger health screen.

I tested out a similar but much more expensive drug response test available from Roche back in 2006. It never seemed to catch on, perhaps because of the $1400 price tag, or the fact that the results could only be sent to a physician. Currently, doctors seem to order pharmacogenomic testing only when there is immediate need; when someone has to go on the blood thinner warfarin, for example. But I think it’s more cost-efficient, and certainly more time-efficient, to have this information as part of an individual’s health record to start with. If you need warfarin immediately, you don’t want to wait for the results of a genetic test. Maybe consumers will be the ones to drive the change.