Gene expression profiling technology refers to a technology that constructs a non-biased cDNA library of cells or tissues in a certain state, performs large-scale cDNA sequencing, collects cDNA sequence fragments, and qualitatively and quantitatively analyzes the composition of its mRNA population or through high-throughput sequencing of the mRNA produced by a species or a specific cell under a specific functional state to study the gene expression difference, depicting the gene expression type and abundance information of the specific cell or tissue under a specific state.