Graphical overview at BDNF gene. The BDNF gene structure and promoter locations are adopted from the study of Pruunsild et al. (2007). Arrow on the top shows the direction of BDNF transcript; exons (green), CpG islands (cyan), and investigated regions for DNA methylation (black) are mapped on NCBI accession number AF411339.1. CpG island were detected by CpGPlot using default parameters (http://www.ebi.ac.uk/Tools/seqstats/emboss_cpgplot/). Number of CpG dinucleotides in each amplicons is shown as lollipops on the lower panel.