Variation in DNA methylation by region of the rat brain. A-F: DNA methylation of Bdnf, Comt, Il1b, Il6, Nrc31, and Tnf in the cerebellum (Ce), cerebral cortex (CE), hippocampus (Hi), hypothalamus (Hy), inferior colliculus (IC), medulla oblongata (MO), midbrain (Mi), pons (Po), superior colliculus (SC), and thalamus (Th). G-H: global DNA methylation estimated by measurement of L1-5utr and L1-orf elements in the same 10 regions of the brain.