Methylation analysis of the DLK1/GTL2 CpG-rich regions. (A) Schematic representation of theDLK1/GTL2 genomic region. The transcription units ofDLK1 and GTL2 are indicated by the boxes with arrows above and below showing the direction of transcription for the maternally and paternally expressed genes, respectively. The hatched ovals represent CpG-rich regions. D1, D2, andD3 (positions 140,543–140,687, 141,101–141,205, and 141,459–141,594 of accession no. AL132711, respectively) andG1, G2, and G3 (positions 65,973–66,085, 66,667–66,793, and 67,780–67,926 of accession no. AL117190, respectively) correspond to sequences within the CpG-rich regions upstream of DLK1 and GTL2, respectively, that were analyzed by bisulphite sequencing. (B) Summary of methylation data. The data shown represent the methylation status of CpG dinucleotides from fetal brain, kidney, liver, and pancreas, which were indistinguishable from one another. All CpG dinucleotides present in these regions are shown. The open and half-filled circles represent unmethylated and hemimethylated CpGs, respectively.
