RESUMEN
Objective:To study dynamic changes of fragile histidine triad(FHIT) gene expression in ionizing radiation injury and radiation carcinogenesis. Methods: BEAS-2B cells were divided into 0.5,1,2,4,8,16 Gy irradiation groups and control group. In 24 h, 72 h and 10 d after irradiation, the expression of FHIT gene was studied with single-cell RT-PCR and DNA sequencing separately. Results: Different types of FHIT gene mutations occured in different phases after irradiation with different doses (All mutations were exon deletion mutations by DNA sequencing), while abnormal FHIT gene was not detected in control group. The percentage of mutation in 0.5,1,2,4,8,16 Gy dose groups was 52.6%,66.7%,57.9%,76.5%,64.7% and 81.3% respectively 24 h after irradiation;17.6%,22.2%,50.0%,47.4%,47.1% and 68.4% respectively 72 h after irradiation;and 21.1%,25.0%,60.0%,57.9%,61.1% and 68.4% respectively 10 d after irradiation. Conclusion: These results suggest that ionizing radiation can cause deletion of FHIT gene.