I'm just trying to get a sense of how critical it is to have a first author publication, or any publication for that matter for MD/PhD programs applying straight out of undergraduate. It seems virtually impossible to get a first-author publication out of my current lab (HHMI Investigator). It is a large, distinguished laboratory with 5+ postdoctoral fellows that produces 20+ publications annually in almost solely in high impact factor journals (5+ journals: Nature, Science, etc.). The past track-record suggests that at best, if I did remain in this laboratory for 2-3 years, I would be looking at third to sixth author paper as an undergraduate. Will I be punished for remaining in the same laboratory for 2-3 years without having a first author publication? Would it be advisable to switch to smaller laboratory that has fewer people working in it to increase the chance of getting authorship at all? Or can a strong recommendation letter from such a distinguished researcher (despite the lack of a publication in time for application, let alone first author) make up for the lack of a publication? Moreover, suppose that one moved around from lab to lab, from internship to internship, during the summers to try different areas within a field or gain new experience at a different lab. Would that be unfavorable to get a breadth of experience that doesn't necessarily result in first-author publications?