Effect of the number of marking enzymes on coverage and redundancy. For each of the RefSeq EST set (Tab. 1), enzyme combinations leading to the best coverage in sequence digestion protocol with two releasing enzymes were used for simulation with MECS. Coverage (filled symbols) and redundancy (open symbols) were plotted against the number of marking enzymes. Triangles connected with dashed lines: mouse; squares connected with dotted lines: human; circles connected with full line: Arabidopsis.