William Blair analyst Brian Weinstein says the recent pullback in shares of GenMark Diagnostics brings a "compelling" valuation. The company' 510(k) clearance from the FDA for its ePlex Blood Culture Identification Gram-Positive panel is "another step toward building a broader menu," Weinstein tells investors in a research note. . This is a "nice year-end win for the company and we believe deserves to be recognized by investors," adds the analyst. He believes the long-term success of GenMark largely depends on its ability to drive placements of its ePlex system, which will likely be dictated by the number of panels that can be run on the system. Weinstein thinks yesterday's news should be seen as a positive update for shares. He keeps an Outperform rating on GenMark.