The HIV dataset [27] contains 55,611 reads from mixture of 10 different 1.5kb-long region of HIV-1 quasispecies, including pol protease and part of the pol reverse transcriptase. The aligned reads length varies from 35bp to 584bp with average about 345bp (see Additional File 1 for details). In contrast to [27] , we do not filter out reads with low-quality scores.