Standard Article

Pseudogene Evolution in the Human Genome

  1. Zhaolei Zhang1,
  2. Deyou Zheng2

Published Online: 17 FEB 2014

DOI: 10.1002/9780470015902.a0020836.pub2

eLS

eLS

How to Cite

Zhang, Z. and Zheng, D. 2014. Pseudogene Evolution in the Human Genome. eLS. .

Author Information

  1. 1

    University of Toronto, Toronto, Ontario, Canada

  2. 2

    Albert Einstein College of Medicine, New York, USA

Publication History

  1. Published Online: 17 FEB 2014

Abstract

Pseudogenes are those regions in a genome that have sequence similarity to functional genes but have decayed and have no obvious functions. It is estimated that the human genome contains more than 10 000 easily recognisable pseudogenes and many more fragmented sequences, that arose mainly through one of the following three mechanisms: duplication, retrotranposition and spontaneous loss of function. The majority of the human retrotransposed (i.e. processed) pseudogenes are primate specific, arising from a burst of retrotransposition activities approximately 45 Ma. Although most of the human pseudogenes are most likely too degenerated to perform a biological function, ∼20% of them exhibit evidence of transcriptional activity based on data from multiple genomic studies. Furthermore, a handful of pseudogene transcripts have been demonstrated experimentally to gain novel functions as noncoding ribonucleic acids (RNAs), indicating that pseudogenes could be a reservoir for evolution innovation.

Key Concepts:

  • Pseudogenes are prevalent in the human genome and other mammalian genomes.

  • Most human pseudogenes are from past retrotranspositions occurring before the split of primate from other lineages.

  • Pseudogenes are a good source of DNA sequences for studying genome evolution.

  • Most human pseudogenes are most likely ‘dead’ but many of them can be transcribed.

  • Some human pseudogenes have adopted functions as noncoding RNAs.

Keywords:

  • pseudogene;
  • human genome;
  • retrotransposition;
  • evolution;
  • noncoding RNAs