This study maps the hallmarks of lung adenocarcinoma using massively parallel sequencing. Researchers analyzed 183 lung adenocarcinoma tumor/normal DNA pairs, revealing a mean exonic somatic mutation rate of 12.0 events per megabase. They identified the majority of genes previously reported as significantly mutated in lung adenocarcinoma, including statistically recurrent mutations in the splicing factor gene U2AF1 and truncating mutations in RBM10 and ARID1A. Analysis of nucleotide context-specific mutation signatures grouped the samples into distinct clusters correlated with smoking history. Whole-genome sequence analysis revealed frequent structural rearrangements, including in-frame exonic alterations in EGFR and SIK2 kinases. The study identified candidate genes that are attractive targets for biological characterization and therapeutic targeting of lung adenocarcinoma. The study also identified significant mutations in 25 genes, including previously reported genes such as TP53, KRAS, EGFR, STK11, KEAP1, NF1, BRAF, and SMAD4, as well as novel candidates such as CHEK2. These genes were associated with various clinicopathologic and genomic features, including smoking status, mutation spectrum clusters, and presence of driver alterations. The study also identified structural variants, including in-frame deletions in EGFR and in-frame kinase domain duplications in SIK2 and ROCK1. These findings suggest that lung adenocarcinoma is a complex disease with multiple genetic alterations that contribute to its pathogenesis. The study highlights the importance of understanding the genetic basis of lung adenocarcinoma to improve diagnosis and treatment. The results demonstrate the power of unbiased, large-scale next-generation sequencing technology in expanding our understanding of tumor biology. The novel mutated genes identified in this study warrant further investigation to determine their biologic, prognostic, and/or therapeutic significance in lung adenocarcinoma, potentially leading to clinical translation and improved outcomes for patients with this deadly disease.This study maps the hallmarks of lung adenocarcinoma using massively parallel sequencing. Researchers analyzed 183 lung adenocarcinoma tumor/normal DNA pairs, revealing a mean exonic somatic mutation rate of 12.0 events per megabase. They identified the majority of genes previously reported as significantly mutated in lung adenocarcinoma, including statistically recurrent mutations in the splicing factor gene U2AF1 and truncating mutations in RBM10 and ARID1A. Analysis of nucleotide context-specific mutation signatures grouped the samples into distinct clusters correlated with smoking history. Whole-genome sequence analysis revealed frequent structural rearrangements, including in-frame exonic alterations in EGFR and SIK2 kinases. The study identified candidate genes that are attractive targets for biological characterization and therapeutic targeting of lung adenocarcinoma. The study also identified significant mutations in 25 genes, including previously reported genes such as TP53, KRAS, EGFR, STK11, KEAP1, NF1, BRAF, and SMAD4, as well as novel candidates such as CHEK2. These genes were associated with various clinicopathologic and genomic features, including smoking status, mutation spectrum clusters, and presence of driver alterations. The study also identified structural variants, including in-frame deletions in EGFR and in-frame kinase domain duplications in SIK2 and ROCK1. These findings suggest that lung adenocarcinoma is a complex disease with multiple genetic alterations that contribute to its pathogenesis. The study highlights the importance of understanding the genetic basis of lung adenocarcinoma to improve diagnosis and treatment. The results demonstrate the power of unbiased, large-scale next-generation sequencing technology in expanding our understanding of tumor biology. The novel mutated genes identified in this study warrant further investigation to determine their biologic, prognostic, and/or therapeutic significance in lung adenocarcinoma, potentially leading to clinical translation and improved outcomes for patients with this deadly disease.