Theoretical Study Of The Dna Chemical Damage Mechanism

DNA is the carrier of heredity information of all biology except few RNA viruses. In the organism, the structure of DNA remains almost unchanged during the process of life activity, and it is the basic condition of organism living and remaining life characters in the filial generation. The structure stability of DNA is not absolute. Many physical or chemical factors within and without organism can lead to the abnormal change of DNA structure, which is called DNA damage. These changes include the unwinding, breaking and crosslinking of DNA double chain, the inserting of intercalators, the dropping bases, the replacing of abnormal bases, the chemical modifying of bases and the changing of relative high-order structure of DNA. Most of DNA damages can be repaired by the repair system within organism. The number of un-repaired DNA damages is thimbleful, but these un-repaired damages maybe produce very important influence on organism. In the replication process, DNA damage can lead to gene mutation. If DNA damages take place on the single strand part of telomere DNA, the physiological function of it maybe changed. If DNA damages appear in the transcription process, the wrong RNA can be produced. DNA damages can lead to the aging, aberration or dead of cells, and further bring forth senescence, tumor and other diseases related to gene. Some DNA damages maybe pass down to the filial generation, which is called gene mutation. Not all of gene mutations are harmful to organism. The advantage mutations maybe remained by organism and finally lead to evolution of organism. So the gene mutation is the necessary condition of biology evolution. The artificial damages of DNA, which is also called artificial induced mutation, are the important methods to curing cancer and other gene related diseased. In the genetic engineering field, the artificial induced mutations are more and more used to improve and create species.Most of DNA damages are brought by chemical factors, and in fact, the damage process is one kind of chemical process. The research of occurring and developing mechanism of DNA damage is the basis of utilizing advantageous damage and inhibiting disadvantageous damages. So it is very important research topic in biology and chemistry. Because the experimental research of the mechanism of DNA damage is difficult to...