CDKN2A and neoplasm: The transcriptome study by Bailey et al. focused on specimens with ≥40% tumor cells and performed deep sequencing of 40% or less, and clarified the relationship between gene mutation and gene expression, and clustered and typed gene expression patterns, and KRAS, TP53, CDKN2A, and SMAD4 were defined as gene mutations by exome analysis [6,8].