Figure 2.

The combinatorial histone modification patterns associated with different chromatin states. The sequence counts are normalized by converting to Z-scores defined as follows:

$${\text{Z}}_{\text{ik}}=({\text{X}}_{\text{ik}}-{\mu }_{\text{i}})/{\sigma }_{\text{i}},$$

where X_ik is the average count for histone modification i=1, 2, 3, 4, 5 within state k=l, 2,…15, μ_i is the average modification level in the truncated genome, and σ_i is the standard deviation of histone modification i in the truncated genome.