Except for the bad promoters, which were unaltered, these generalized motifs were selected to each cover roughly twice as many bases as their equivalents in the original motif list. Together they covered 2.8% (74 Mb) of the autosomal bases in HG19. The generalized motifs included 7.5% (1.7 Mb) of the bases previously excluded as probable biological variations. This enrichment may indicate that the biological variation filters excluded bases whose low coverage had a non-biological origin, or it may indicate a correlation between bias motifs and sites with high mutation rates.
