title: Different ras gene mutational frequencies in thyroid papillary carcinomas in Japan and Thailand.
abstract: The incidence and pattern of ras oncogene mutations in human malignancies demonstrate geographic and racial differences. For example, specificity of alterations is found in cholangiocellular carcinomas in Thai patients with a different etiology from those in Japanese patients. In the present study, a comparison of ras gene mutations in thyroid papillary carcinomas from Japanese and Thai patients was performed using single-strand conformation polymorphism and direct sequencing analyses. The incidence of ras mutation differed markedly in Japanese (two of 24 carcinomas, 8.3%) and Thai (five of 10 carcinomas, 50%) patients. In addition, all but one ras mutation occurred at codon 12 of the K-ras gene in the Thai cases. These results suggest that thyroid cancers in Thailand may be due to specific genetic and/or environmental factors.
authors.affiliation: The Second Department of Pathology, Nara Medical University, Kashihara, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Naito
authors.forename: C
authors.initials: C
authors.lastname: Pairojkul
authors.forename: Y
authors.initials: Y
authors.lastname: Kitahori
authors.forename: K
authors.initials: K
authors.lastname: Yane
authors.forename: H
authors.initials: H
authors.lastname: Miyahara
authors.forename: N
authors.initials: N
authors.lastname: Konishi
authors.forename: T
authors.initials: T
authors.lastname: Matsunaga
authors.forename: Y
authors.initials: Y
authors.lastname: Hiasa
mesh_terms: D000328:Adult; D000368:Aged; D002291:Carcinoma, Papillary / Q000235:genetics*; D002648:Child; D005260:Female; D011905:Genes, ras; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D013785:Thailand / Q000453:epidemiology; D013964:Thyroid Neoplasms / Q000235:genetics*