Corra-generated volcano plot of human type 2 diabetes plasma analyses. N-glycosite peptides were isolated for human plasma samples and analyzed via LC-MS, as described under Methods. Randomized, triplicate analyses were performed for each of 22 human plasma samples, 13 controls (NGT: normal glucose tolerance) and 9 from newly diagnosed cases of type 2 diabetes (DB). Volcano plot displays the 4,240 features that aligned across a minimum of 3 LC-MS runs. The x-axis shows observed log fold change in aligned feature mean intensities between the two sample groups, NGT and DB. The y-axis shows B statistics log Odds for non-random differential abundance obtained for each aligned feature. Red colored dots represent the 400 top-ranked features (in terms of log Odds) that were subsequently targeted for MS/MS identification. A log Odds value of 0 corresponds to a 50% probability non-random differential abundance, and a log Odds of 2.2 to a 90% probability.
Brusniak et al. BMC Bioinformatics 2008 9:542 doi:10.1186/1471-2105-9-542