Encyclopedia of Behavioral Medicine

2013 Edition
| Editors: Marc D. Gellman, J. Rick Turner

Insertion/Deletion Polymorphism

Reference work entry
DOI: https://doi.org/10.1007/978-1-4419-1005-9_706


An insertion/deletion polymorphism, commonly abbreviated “indel,” is a type of genetic variation in which a specific nucleotide sequence is present (insertion) or absent (deletion). While not as common as SNPs, indels are widely spread across the genome. Indels comprise a total of 3 million of the 15 million known genetic variants (The 1000 Genomes Project Consortium, 2010). An indel in the coding region of a gene that is not a multiple of 3 nucleotides results in a frameshift mutation. Shifting the reading frame and the DNA transcript sequence may now code for an entirely different set of amino acids or result in a premature stop codon, altering the protein structure and function. Indel variants with multiples of 3 nucleotides result in a protein with extra amino acids (insertion) or loss of amino acids (deletion), but the other amino acids are not affected. The site of the indel in the gene is important since it determines which part of the protein is affected, since not...

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References and Readings

  1. Lewis, R. (2005). Human genetics. Concepts and applications (7th ed.). Boston: McGraw-Hill Science/Engineering/Math.Google Scholar
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  3. Strachan, T., & Read, A. P. (2003). Human molecular genetics (3rd ed.). London/New York: Garland Science/Taylor & Francis Group.Google Scholar
  4. The 1000 Genomes Project Consortium. (2010). A map of human genome variation from population-scale sequencing. Nature, 467(7319), 1061–1073. doi:10.1038/nature09534.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, New York 2013

Authors and Affiliations

  1. 1.Department of PsychiatryColumbia University Medical CenterNew YorkUSA
  2. 2.Broad InstituteCambridgeUSA