Rapid detection of K-ras gene point mutation in pancreatic adenocarcinoma by Pyrosequencing

Abstract

Objective To establish a method for detecting K-rag gene point mutation in pancreatic adenocarcinoma based on the pyrosequencing and to compare its performance with that of Sanger sequencing.Methods Genomic DNA was extracted from formalin-fixed,paraffin-embedded pancreatic tissues including 49 pancreatic adenocarcinoma,10 normal pancreas,11 chronic pancreatitis,18 benign pancreatic tumor,7 insulin carcinoma,9 ampullary carcinoma,7 bile duct carcinoma and 7 duodenum papillary adenocarcinoma tissues.K-rag gene point mutations at codon 12 were analyzed by pyrosequencing and Sanger sequencing,respectively.Results No mutant K-ras gene Wag detected in normal pancreas,chronic pancreatitis,benign pancreatic tumor,insulin carcinoma,ampullary carcinoma,bile duct carcinoma and duodenum papillary adenocarcinoma tissues by either pyrosequencing or Sanger sequencing.K-rag gene point mutation was detection rate in pancreatic adenocarcinoma tissues was 71.4%(35/49)by pyrosequencing and 61.2%(30/49)by Sanger sequencing,respectively.Conclusions Pyrosequencing is more sensitive than Sanger sequencing and is also accurate,rapid and of high throushput in detecting mutant K-ras gene.It may serve as a practical method for fast batch analysis of clinical samples. Key words: Pancreatic neoplasms; Genes,rag; Point mutation; Phosphoric acids; Sequence analysis,DNA; Pyrosequencing