Detailed methylation status of CpG islands (CGIs) in the Kip2/Lit1 subdomain. At the top is a schematic gene cluster based on the sequences obtained in the Kip2/Lit1 subdomain. The numbers above the line show a summation based on the sequences, which includes one gap. The imprinting status is shown by filled boxes (paternally expressed), open boxes (maternally expressed), and gray boxes (biallelic expression). Exons of Kvlqt1 are depicted as vertical bars. The transcriptional orientation of genes is indicated by horizontal arrowheads. Middle, a schematic CGI. According to sequencing results, a total of 10 CGIs (CGIs 1–10) were identified. The thick horizontal lines below the line indicate the sequenced regions, with GenBank accession nos. Bottom, the detailed methylation status of CGIs in somatic tissues. Each circle represents a CpG dinucleotide on the strand: (●) a methylated cytosine; (○) an unmethylated cytosine. Paternal and maternal alleles were distinguished by DNA polymorphism, as presented in Table 1. Bisulphite sequencing was performed in adult kidney, embryo (10.5 dpc), and placenta (8.5 dpc) DNAs. The placenta was used when it was proved the gene was expressed monoallelically in this tissue. In adult kidney, at least 10 clones were sequenced from each parental allele. Primers are described in Methods. The first 20 CpGs of the analyzed CGIs are presented and numbered from 1–20 from the left. F₁ hybrid mice used were all BPF₁. M, maternal; P, paternal.