Hairpin Formation during DNA Synthesis Primer Realignmentin Vitro in Triplet Repeat Sequences from Human Hereditary Disease Genes*

  title={Hairpin Formation during DNA Synthesis Primer Realignmentin Vitro in Triplet Repeat Sequences from Human Hereditary Disease Genes*},
  author={Keiichi Ohshima and R. D. Wells},
  journal={The Journal of Biological Chemistry},
  pages={16798 - 16806}
Genetic expansion of DNA triplet repeat sequences (TRS) found in neurogenetic disorders may be due to abnormal DNA replication. We have previously observed strong DNA synthesis pausings at specific loci within the long tracts (>∼70 repeats) of CTG·CAG and CGG·CCG as well as GTC·GAC by primer extensions in vitro using DNA polymerases (the Klenow fragment ofEscherichia coli DNA polymerase I, the modified T7 DNA polymerase (Sequenase), and human DNA polymerase β). Herein, we have isolated and… 

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