Projects

The ICGC was established in 2007 and concluded its mis-sion to define the genomes of 25,000 primary untreated cancers (the 25K Initiative) in 2018. The ICGC solved numerous data governance, ethical and logistical challenges to make global genomic data sharing for cancer a reality, providing the interna-tional community with comprehensive genomic data for many cancer types. As the second ICGC initiative, the ICGC launched a “Pan-Cancer” Whole Genome project (PCAWG) in 2014, in which WGS data together with RNA-Seq of 2834 samples were analyzed in uniform pipelines within the same computational environment and cloud computing. RIKEN has been contributing to this project as a member of a technical working group and as PI/researchers in working groups for several projects. In February 2020, PCAWG published more than 20 papers in Nature and Nature sister journals and wrapped up. The RIKEN group has been focusing on mitochondria genome (mtDNA) mutations in cancer WGS data and found instances of somatic transfer of mitochon-drial DNA into the cancer nuclear genome. They also observed excessive accumulation of high-allele-frequency truncating muta-tions in mtDNA, specifically in kidney cancers.

Figure: A Circos plot representing somatic mtDNA nuclear transfer events in a bladder cancer genome. Human chromosomes and mtDNA (MT) are shown in the outer layer. Chro-mosomal rearrangements are shown as gray curves and mtDNA nuclear transfers are represented by red curves.