Studying epigenetic effect on evolution of virus genomes

Abstract

DNA methylation is an epigenetic mechanism which play imported role in vertebrate genome and which is used to regulate many cellular processes that include gametogenesis, early embryogenesis, cellular differentiation and development, genomic imprinting. Viruses have very short period of reproductive life cycle and higher rate of evolution; we should expect observable changes in genome over relatively shorter time periods. The changes are based on host compatibility. We attempted to study Human viruses causing common diseases and having DNA genome or DNA intermediate in there genome replication. They have been selected to study changes in genome structure over stipulated time. Our data present evidence that in small viruses (HBV and adenovirus) the CpG is under-representative and TpG and CpA is over- representative. In large DNA viruses (cytomegalovirus) the CpG is not under-representative except in EBV where CpG is under-representative. Our finding based on Multiple Sequence Alignment on evolution of HBV genome to support a novel perspective that CpG is mutated to TpG/CpA.