title: Differential detection of KRAS mutations in codons 12 and 13 with a modified loop-hybrid (LH) mobility shift assay using an insert-type LH-generator.
abstract: BACKGROUND
  The loop-hybrid mobility shift assay (LH-MSA) was previously developed for the rapid detection of the EGFR mutation L858R for predicting clinical responses to gefitinib in lung cancer. Recently, clinical importance of determining KRAS mutations has been demonstrated in colorectal tumors as tumors harboring mutated KRAS genes were not responsive to therapy with EGFR-targeted antibodies such as cetuximab.
  
  
  METHODS
  We developed a new version of the LH-MSA using an insert-type LH generator that was capable of detecting all 12 KRAS mutations in codons 12 and 13.
  
  
  RESULTS
  Feasibility evaluation was performed with this new LH-MSA on 215 colorectal cancer specimens. KRAS codon 12 mutations were detected in 23% specimens and codon 13 mutations in 6.5% specimens by LH-MSA at a rate better than by direct sequencing.
  
  
  CONCLUSIONS
  Using the new method, the G13D mutation was readily distinguishable from other KRAS mutations in codon 12 and, therefore, would be advantageous for clinical applications.
authors: Molecular Pathology and Genetics Division, Kanagawa Cancer Center Research Institute, Yokohama, Japan.
authors: Shoichi
authors: S
authors: Matsukuma
authors: Mitsuyo
authors: M
authors: Yoshihara
authors: Tetsuji
authors: T
authors: Suda
authors: Manabu
authors: M
authors: Shiozawa
authors: Makoto
authors: M
authors: Akaike
authors: Tomokazu
authors: T
authors: Ishikawa
authors: Shiro
authors: S
authors: Koizume
authors: Yuji
authors: Y
authors: Sakuma
authors: Yohei
authors: Y
authors: Miyagi
mesh_terms: D001483:Base Sequence; D003062:Codon; D015179:Colorectal Neoplasms / Q000235:genetics; D017931:DNA Primers; D011905:Genes, ras; D006801:Humans; D009154:Mutation
chemical_list: D003062:Codon; D017931:DNA Primers