We found that the content of Class IIa HDACs, namely HDAC4 (1.00±0.11 vs. 0.70±0.03 of CH mice, p<0.05, n = 5–8) and HDAC5 (1.00±0.25 vs. 0.57±0.08 of CH, p<0.05, n = 5–8) were elevated in the liver of T2D mice whereas the expression of HAT1 was not altered in T2D mice (1.00±0.08 vs. 0.80±0.04 of CH mice, p>0.05, n = 5–8). The gene discussed is HDAC5; the disease is type 2 diabetes mellitus.