Tan has made great contributions to the development of genetics in China, especially in the research on the evolution of genetic structure of Drosophila population and the genetic variation of Harmonia axyridis strains, which provides important arguments for the establishment of modern evolutionary synthesis theory. Tan has been engaged in genetics teaching and research for 70 years, and has successively taught general biology, comparative anatomy of vertebrates, embryology, genetics, cytology, advanced experimental chemistry, cytogenetics, Darwinism, radiation genetics, protozoology and other courses. He has published more than 100 research papers and academic articles, mainly including Selected Tan Papers (1987, Science Press) and Tan Wenxuan (1992, Zhejiang Science and Technology Press). His research work mainly involves cytogenetics, population genetics, radiation genetics, toxicology genetics, molecular genetics and genetic engineering of ladybugs, fruit flies, macaques, humans and plants. It provides an important argument for establishing modern comprehensive evolution theory. During his teaching in Zhejiang University, he discovered the mosaic dominance phenomenon of ladybug stain inheritance. It has aroused great response from the international genetics community and is considered as a great contribution to the development of classical genetics. Mr. Tan insisted on scientific truth and devoted his life to genetics. In 2009, Tan was selected as the first person in genetics in China, world record association and China.