Summary of bisulfite sequencing analyses of male heart (H) and spleen (S) DNA in the RYR2 gene sequence represented by BAC clone RP11-47A4 (AL391809). More striking methylation differences between these tissues are observed at dispersed CpGs outside of the CpG island (top) than in the island (bottom). Each CpG analyzed by bisulfite sequencing is represented by a fraction in which the denominator is the total number of sequenced clones of PCR products amplified from bisulfite-converted DNA, and the numerator is the number of times methylation was detected at that site. Data for CpGs contained within Hpa II sites (CCGG) are shaded gray. The results for distributed CpG sites not included in CpG islands are indicated along the top, with their relative positions in the AL391809 sequence indicated. Vertical bars separate the sites on different PCR amplicons. The CpG island is highlighted by the gray vertical bar in the schematic of the AL391809 sequence and expanded below to indicate the position of exon 1 of RYR2 gene (white) and the GC boxes (dark gray). Two PCR products (P1 and P2) containing multiple CpGs within this CpG island were analyzed by bisulfite sequencing, and the results are indicated at the bottom of the figure. Boxes contain overall average methylation levels for heart (H) and spleen (S) for CpGs sampled outside of the CpG island (top) and for CpGs sampled within the CpG island (bottom).