LAUSR

In contrast to bottom‐up LC‐MS only 2DE‐MS can separate and detect a huge number of human protein species. Kwiatkowski et al. (in this issue) established parameters to estimate the amount of protein speciation for each human protein. Proteins identified in 2DE‐MS approaches showed more protein speciation than in bottom‐up LC‐MS. The authors state that protein speciation is likely to increase the chance of proteins to be determined in 2‐DE/MS, though admitting that low‐sensitivity 2DE‐MS methods were used in this study. In agreement with Kwiatkowski et al., we are convinced that the difference between 2DE‐MS and bottom‐up LC‐MS will disappear, if high‐resolution 2DE is combined with identification by a high‐sensitivity LC‐Orbitrap‐MS. Meta‐analysis of proteomic data is surely a promising tool, though the technological progress in 2DE and MS has to reach a plateau to enable useful comparisons.