Insertion (genetics)

An illustration of an insertion at chromosome level

In genetics, an insertion (also called an insertion mutation) is the addition of one or more nucleotide base pairs into a DNA sequence. This can often happen in microsatellite regions due to the DNA polymerase slipping. Insertions can be anywhere in size from one base pair incorrectly inserted into a DNA sequence to a section of one chromosome inserted into another. The mechanism of the smallest single base insertion mutations is believed to be through base-pair separation between the template and primer strands followed by non-neighbor base stacking, which can occur locally within the DNA polymerase active site.[1] On a chromosome level, an insertion refers to the insertion of a larger sequence into a chromosome. This can happen due to unequal crossover during meiosis.

N region addition is the addition of non-coded nucleotides during recombination by terminal deoxynucleotidyl transferase.

P nucleotide insertion is the insertion of palindromic sequences encoded by the ends of the recombining gene segments.

Trinucleotide repeats are classified as insertion mutations[2][3] and sometimes as a separate class of mutations.[4]

  1. ^ Banavali, Nilesh K. (2013). "Partial Base Flipping is Sufficient for Strand Slippage near DNA Duplex Termini". Journal of the American Chemical Society. 135 (22): 8274–8282. doi:10.1021/ja401573j. PMID 23692220.
  2. ^ "Mechanisms: Genetic Variation: Types of Mutations". Evolution 101: Understanding Evolution For Teachers. University of California Museum of Paleontology. Archived from the original on 2009-04-14. Retrieved 2009-09-19. ] Understanding Evolution For Teachers Home. Retrieved on September 19, 2009
  3. ^ Brown, Terence A. (2007). "16 Mutations and DNA Repair". Genomes 3. Garland Science. p. 510. ISBN 978-0-8153-4138-3.
  4. ^ Faraone, Stephen V.; Tsuang, Ming T.; Tsuang, Debby W. (1999). "5 Molecular Genetics and Mental Illness: The Search for Disease Mechanisms: Types of Mutations". Genetics of Mental Disorders: A Guide for Students, Clinicians, and Researchers. Guilford Press. p. 145. ISBN 978-1-57230-479-6.