CpG Islands: A Historical Perspective

  • Francisco AntequeraEmail author
  • Adrian Bird
Part of the Methods in Molecular Biology book series (MIMB, volume 1766)


The discovery of CpG islands (CGIs) and the study of their structure and properties run parallel to the development of molecular biology in the last two decades of the twentieth century and to the development of high-throughput genomic technologies at the turn of the millennium. First identified as discrete G + C-rich regions of unmethylated DNA in several vertebrates, CGIs were soon found to display additional distinctive chromatin features from the rest of the genome in terms of accessibility and of the epigenetic modifications of their histones. These features, together with their colocalization with promoters and with origins of DNA replication in mammals, highlighted their relevance in the regulation of genomic processes. Recent approaches have shown with unprecedented detail the dynamics and diversity of the epigenetic landscape of CGIs during normal development and under pathological conditions. Also, comparative analyses across species have started revealing how CGIs evolve and contribute to the evolution of the vertebrate genome.

Key words

CpG islands DNA mehylation Chromatin Transcription Evolution 


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Authors and Affiliations

  1. 1.Instituto de Biología Funcional y GenómicaConsejo Superior de Investigaciones Científicas (CSIC)/Universidad de SalamancaSalamancaSpain
  2. 2.Wellcome Trust Centre for Cell BiologyUniversity of EdinburghEdinburghUK

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