Ridanpää M, Husgafvel-Pursiainen K
Institute of Occupational Health, Helsinki, Finland.
Hum Mol Genet. 1993 Jun;2(6):639-44. doi: 10.1093/hmg/2.6.639.
Point mutations in the ras oncogenes are very common in lung cancers as well as in many of the other solid tumours. To effectively examine the occurrence of these mutations in a large number of tumour samples, we have applied denaturing gradient gel electrophoresis (DGGE) for the analysis of point mutations of the K-ras and N-ras genes, using GC-clamped, PCR-amplified DNA fragments. Among the 68 tumour DNA samples, we detected 14 mutations in the K-ras gene. This was 78% of the mutations identified by oligonucleotide hybridization. Altogether, eight of the nine different kinds of base substitutions found in the tumour samples were detected by the DGGE assay, representing substitutions at codons 12, 13, and 61 of the K-ras gene. Six of the detected mutations were guanine to thymine transversions at codon 12; this was the most common type of alteration. On the basis of our experience, the present non-radioactive DGGE analysis seems to be readily applicable for detection of the mutations in the K-ras and N-ras genes. Types of ras gene mutations frequent in adenocarcinomas of the lung are also discussed.
ras癌基因中的点突变在肺癌以及许多其他实体瘤中非常常见。为了有效检测大量肿瘤样本中这些突变的发生情况，我们应用变性梯度凝胶电泳（DGGE），使用GC夹、PCR扩增的DNA片段来分析K-ras和N-ras基因的点突变。在68个肿瘤DNA样本中，我们在K-ras基因中检测到14个突变。这占寡核苷酸杂交鉴定出的突变的78%。通过DGGE分析总共检测到肿瘤样本中发现的9种不同碱基替换中的8种，代表K-ras基因第12、13和61密码子处的替换。检测到的6个突变是第12密码子处的鸟嘌呤到胸腺嘧啶的颠换；这是最常见的改变类型。根据我们的经验，目前的非放射性DGGE分析似乎很容易用于检测K-ras和N-ras基因中的突变。还讨论了肺腺癌中常见的ras基因突变类型。
