目的研究应用特殊设计的单链寡核苷酸链(ODN)纠正点突变的方法。方法以Ames试验体系为基础,应用ODN纠正TA102中组氨酸操纵子基因的点突变。结果将ODN直接加入到正常状态下的细菌中检测不出有纠正率,而用CaCl2法将TA102制备成感受态细菌后可以得到一定的纠正率(10-5)。结论ODN能够纠正TA102中组氨酸操纵子基因的点突变,可以建立起以Ames试验体系为基础的研究寡核苷酸链纠正点突变的实验方法。 Objective To investigate a method to correct point mutations using a specially designed single-stranded oligonucleotide (ODN) strand. Methods Based on the Ames test system, point mutations of the histidine operon gene in TA102 were corrected by ODN. Results There was no correction rate when the ODN was directly added to the bacteria in the normal state. However, a certain correction rate (10-5) was obtained after the TA102 was prepared into the competent bacteria by the CaCl2 method. Conclusion ODN can correct the point mutation of the histidine operon in TA102 and establish an experimental method to correct the point mutation in oligonucleotide chain based on Ames test system.