(A) Schematic representation of the human PDYN gene and 5' upstream region (3 kbp from the transcription start site, TSS). ATG is the translation start site. Shown are the distribution of CpG dinucleotides, the location of the CpG island, and the two other CpG-rich regions, cluster A and cluster B. (B) The sequences of the CpG island, cluster A and cluster B that were used for DNA methylation analyses. The position of CpG sites in the CpG island and in cluster A are shown relative to +1 of TSS. The CpG cluster B is located at nucleotides from 346 to 610, relative to the first nucleotide of the exon 4. The TATA-box and putative transcription sites are underlined. The SNP rs1997794 (A to G) affects CpG site #23 and alters the canonical binding site for transcription factor AP-1.