基因是指能够合成有功能的蛋白质或RNA所必须的全部DNA序列(除部分病毒RNA外),即一个基因不仅包括编码蛋白质或RNA的核酸序列,还应包括为保证转录所必需的调控序列。目前,普遍认为人类疾病的发生都直接或间接与基因受损有关,遗传因素是内因,环境因素是外因,人类疾病是遗传因素(基因组信息)与环境因素相互作用的结果。然而,暴露于相同环境致病因素的人群中只有一部分人会发病,个体之间存在的这种差异性被称为遗传易感性。遗传易感性的形成是由于在进化过程中遗传物质不断变异,导致一种基因可能有几种 A gene refers to all the DNA sequences (except some viral RNAs) that are necessary for the synthesis of a functional protein or RNA. That is, a gene includes not only a nucleic acid sequence encoding a protein or RNA, but also regulatory sequences necessary for ensuring transcription. At present, it is generally accepted that the occurrence of human diseases is directly or indirectly related to genetic damage. Genetic factors are internal causes. Environmental factors are exogenous factors. Human diseases are the result of the interaction between genetic factors (genome information) and environmental factors. However, only a fraction of the population exposed to the same environmental causative agent is affected and this discrepancy between individuals is called genetic predisposition. The formation of genetic susceptibility is due to the constant evolution of genetic material, resulting in a gene may have several