Inhibition of DNA synthesis by K+-stabilised G-quadruplex promotes allelic preferential amplification

FEBS Lett. 2004 Jul 30;571(1-3):112-8. doi: 10.1016/j.febslet.2004.06.062.


PCR preferential amplification consists of the inefficient amplification of one allele in a heterozygous sample. Here, we report the isolation of a GC-rich human minisatellite, MsH43, that undergoes allelic preferential amplification during PCR. This effect requires the existence of a (TGGGGC)(4) motif that is able to form a G-quadruplex in the presence of K(+). This structure interferes with the DNA synthesis of the alleles harbouring this motif during PCR The present results are the first demonstration that the formation of G-quadruplex can be one of the mechanisms involved in some kinds of preferential amplification.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • DNA Methylation
  • DNA Replication / physiology*
  • Female
  • Fetus
  • Gene Amplification
  • Humans
  • Liver / embryology
  • Liver / physiology
  • Male
  • Molecular Sequence Data
  • Pedigree
  • Polymerase Chain Reaction / methods
  • Potassium / pharmacology*


  • Potassium