RUNX3 and COVID-19: For example, the clusters can be explained by factors such as GFI1B, CEBPB, and RUNX3 in clustering PBMC data, by Cebpe in clustering hematopoiesis data, and by HMGB2 in clustering COVID-19 data, allowing the identification of what type of cells the clusters represent and what characteristics they possess, even within similar cell types, without looking at GO terms, using information from GRN/MDS.