RT Journal A1 Long, Yongkang A1 Zhang, Bin A1 Tian, Shuye A1 Chan, Jia Jia A1 Zhou, Juexiao A1 Li, Zhongxiao A1 Li, Yisheng A1 An, Zheng A1 Liao, Xingyu A1 Wang, Yu A1 Sun, Shiwei A1 Xu, Ying A1 Tay, Yvonne A1 Chen, Wei A1 Gao, Xin T1 Accurate transcriptome-wide identification and quantification of alternative polyadenylation from RNA-seq data with APAIQ JF Genome Research JO Genome Research YR 2023 FD April 01 VO 33 IS 4 SP 644 OP 657 DO 10.1101/gr.277177.122 UL http://genome.cshlp.org/content/33/4/644.abstract AB Alternative polyadenylation (APA) enables a gene to generate multiple transcripts with different 3′ ends, which is dynamic across different cell types or conditions. Many computational methods have been developed to characterize sample-specific APA using the corresponding RNA-seq data, but suffered from high error rate on both polyadenylation site (PAS) identification and quantification of PAS usage (PAU), and bias toward 3′ untranslated regions. Here we developed a tool for APA identification and quantification (APAIQ) from RNA-seq data, which can accurately identify PAS and quantify PAU in a transcriptome-wide manner. Using 3′ end-seq data as the benchmark, we showed that APAIQ outperforms current methods on PAS identification and PAU quantification, including DaPars2, Aptardi, mountainClimber, SANPolyA, and QAPA. Finally, applying APAIQ on 421 RNA-seq samples from liver cancer patients, we identified >540 tumor-associated APA events and experimentally validated two intronic polyadenylation candidates, demonstrating its capacity to unveil cancer-related APA with a large-scale RNA-seq data set.