Concurrent mutations of K-ras oncogene at codons 12 and 22 in colon cancer.
K-ras mutation is the most common oncogenic alteration in various human cancers including colorectal carcinomas. Point mutations have the potential to activate the K-ras gene if they occur in the critical coding sequences. Almost all of these mutations have been localized in codons 12, 13 and 61. We report a case of colon cancer presenting point mutations at both codons 12 and 22 of the K-ras gene. PCR-SSCP and subsequent sequencing revealed that GGT (glycine, wild-type) to AGT (serine) substitution at codon 12 and CAG (glutamine, wild-type) to CGG (arginine) substitution at codon 22 occurred in the same allele.
Department of Surgery, Jichi Medical School, Minami Kawachi, Tochigi, Japan.
Yasuyuki
Y
Miyakura
Kokichi
K
Sugano
Noriko
N
Fukayama
Fumio
F
Konishi
Hideo
H
Nagai
D001483:Base Sequence; D003062:Codon / Q000235:genetics*; D003110:Colonic Neoplasms / Q000235:genetics*; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D017354:Point Mutation
D003062:Codon