Methylation profiles of four lobes of the brain are similar. (A) Methylation profiles of four different brain regions from a female donor, each measured using the same individual's spleen as a reference. Clones highlighted in black have log2 ratios that deviate in either direction from the median (set at 0) by >4.88 median absolute deviation (MAD) units calculated from the region in 1q marked 'MAD'. See Figure 4 for additional details. (B and C) X-Y scatter plots illustrating the positive correlation between log2 ratios measured for different brain parts from female donor (each relative to her spleen). (B) Plot displaying a comparison of occipital lobe-versus-spleen and cerebellum-versus-spleen ratios from the female donor (F1 replicates in all cases); (C)Plot showing a comparison of pons-versus-spleen and cerebellum-versus-spleen ratios; (D)Plot showing a comparison of medulla-versus-spleen and cerebellum-versus-spleen ratios. Pearson correlation coefficients (R2) are 0.43, 0.31 and 0.29 for B, C and D, respectively, and indicate significant association at the P < 10-15 level.