Along the course of occurrence and development of liver cancer,the corresponding somatic cells accumulate some important genetic variations.These variations may be divided into two categories.For the genetic changes closely related to etiology of liver cancer,the well-known cases include insertion and integration of the hepatitis B virus(HBV) DNA after infection,and mutations at site 249 of the tumor suppressor gene p53 induced by exposure to aflatoxin B1.The secondary genetic changes include amplification and deletion of certain chromosome regions,mutations in p53 at the sites other than 249,as well as the mutational activation of the Wnt/β-catenin signal pathway.The tumor cells with these genetic variations may gradually become the dominant clones under evolutionary selection.Besides,identification of genetic susceptible against risk of liver malignancy is also an important aspect of research in this field. Along the course of occurrence and development of liver cancer, the corresponding somatic cells accumulate some important genetic variations. The variations may be divided into two categories. For the genetic changes closely related to etiology of liver cancer, the well-known cases include insertion and integration of the hepatitis B virus (HBV) DNA after infection, and mutations at site 249 of the tumor suppressor gene p53 induced by exposure to aflatoxin Bl. The secondary genetic changes include amplification and deletion of certain chromosome regions, mutations in p53 at the sites other than 249, as well as the mutational activation of the Wnt / β-catenin signal pathway. tumor cells with these genetic variations may gradually became the dominant clones under evolutionary selection. Besides, identification of genetic susceptibles against risk of liver malignancy is also an important aspect of research in this field.