Development of new technologies in the genomics field has enabled us to examine millions of genetic variations as well as whole-genome or-exome sequences very rapidly at the very cheap cost.Taking the advantages of the large-scale SNP typing systems and next generation DNA sequencers, the international collaborative groups including us have been accumulating a huge body of information and successfully identified dozens of germline variations in genes susceptible to various cancers as well as thousands of somatic mutations in various types of human cancers.