Non-coverage rates at the domain level. “AA” denotes the AntarcticaAquatic dataset, “AM” denotes the AcidMine dataset, “BM” denotes the BisonMetagenome dataset, “GW” denotes the GutlessWorm dataset, “HG” denotes the HumanGut dataset and “Ave” is the arithmetic mean of the 7 non-coverage rates of the metagenomic datasets. Mismatches in the last 4 nucleotides were not allowed. Refer to Additional file 1: Figure S1B for the normalized results. Refer to Additional file 2: Figure S2 for the phylum non-coverage rates.