Figure 2

Extensive H3 cleavage is evident in approximately one-third of PBMC histone samples, but it does not affect measures of H3K36me2 and H3K79me2. Total H3 was measured in an additional 32 histone PBMC samples from the FACT study and in histones from calf thymus (Sigma-Aldrich). H3K36me2 was also measured in 22 of the PBMC samples (Samples 1–22), and H3K79me2 was measured in calf histones and in ten of the PBMC samples (Samples 23–32).