Earlier this month employees at most of 7500 Walgreens pharmacies geared up to stock a new item on their shelves: a saliva sampler for personal genetic testing. On May 11, officials at Pathway Genomics, a San Diego-based biotech firm, announced they’d sell over-the-counter spit kits for around $25 through an arrangement with the retailer. A curious consumer could follow the simple package instructions and send their stuff in a plastic tube, provided in a handy box with pre-paid postage, for DNA analysis.