A primary CpG island was identified from nucleotides -48 to +588 bp (CG content, 74.1%; CpG ratio, 0.95) as shown in Fig. 1A. To investigate whether DNA methylation is related to the expression of CREG, we overexpressed DNMT1, DNMT3A, or DNMT3B in HUVECs by adenovirus infection to mimic hyper-methylation, and then evaluated changes in CREG expression. This evidence concerns the gene CREG1 and adenoviridae infectious disease.