The discovery of genes has changed a lot of our understanding of life. If we think of the human body as a building, the blueprint for it is in the genome. Each of us has 23 pairs of chromosomes, and if we look at each pair of chromosomes as a line, then each paragraph has its own code, and this code is the gene, for example, when the cell divides and when the cell apoptosis, all of these have rules and work through gene expression, including the fact that each of us grows differently, all of which is determined by our genes. Genes are the most important blueprint of our life, equivalent to the functional software of our body. Nowadays, when we talk about cancer treatment, we talk about specific genetic changes, about targeting, about molecular pathology, and some future individualized treatments, all of which are related to genes. In fact, what is cancer, in one sentence, cancer is a genetic disease. In the process of turning a normal cell into a cancer cell, several important genetic mutations need to occur, resulting in abnormal differentiation and growth of normal cells, and this root cause is due to genetic changes. There are many types of tumors, for example, brain tumors, and there are hundreds of types of tumors, and there are many different subtypes of glioma alone. In fact, the genetic changes of each person are different, which leads to different tumor development, pathology, drug response and prognosis of patients. For example, patients carrying ALK fusion protein only account for 5% of the total number of lung cancer patients. It is not right to give the same agent to a hundred patients, because 95% of them do not respond and the drugs are very expensive. Then there is EGFR, for example, which also has mutations only in certain patients. If we say we get a universal drug and give it to so cancer patients, I think it is still not possible to see at the moment. But at present, using one or two targeted drugs is also far from enough, because there will be resistance and recurrence problems, and now we have to compound the drugs. There are many good programs for immunotherapy, but to achieve the best therapeutic effect, immunotherapy should explain the special genetic changes in the tumor and the special tumor antigens. With genomics, such as the second-generation sequencing that we love, and possibly more advanced sequencing in the future, we can use high-throughput, rapid and inexpensive means to decipher the genes of each tumor patient and discover what the genetic mutations in the “black box” really are. Genomic research has now become the most important and powerful tool in cancer treatment, revealing the specificity of each individual’s disease and giving the patient the most effective and clear treatment choice.