Basic Research - Cancer(구연) (E-017) Prioritizing Cancer Predisposition Variants in a Family with Hereditary Prostate Cancer Department of Urology, Kyung Hee University, School of Medicine Department of Pathology, Kyung Hee University, School of Medicine¹ Dong Soo Kim, Seung Hyun Jeon, Sun-Ju Lee, Choong Hyun Lee, Sung-Goo Chang, Ji-Youn Sung¹, Sang Hyub Lee Background A family that has more than five prostate cancer patients for three generations was investigated. We analyzed their blood and prostate tissues whether there are mutations of specific genes to identify a novel candidate gene for prostate cancer among Asian populations. Methods Whole exomes of nine family members of a single family were sequenced. According to the pedigree, we grouped the samples into three groups; affected, unknown-sibling, and unknown-offspring. The variants observed in all the three affected samples are further filtered with the condition of absence of the variant in all the samples in unknown-sibling group. Results There were no variants mapped to known cancer predisposition genes which is defined as genes whose variants have been reported as pathogenic or likely pathogenic for CLDN matched with ‘cancer’ or ‘prostate’ from ClinVar database (as of 2018-12-02). To further investigate the rare variants, we calculated the distance between those variants and GWAS catalogue SNPs. All prostate cancer patients had variants of CCDC170 and PANO1. Within 10,000 bp, there were two pairs of rare variants and GWAS SNPs. The frame-shift deletion of CCDC170 is located near rs3757318, while the 3bp duplication of PANO1 is located near rs659781. Conclusion The frame-shift deletion of CCDC170 and the 3bp duplication of PANO1, which may affect ESR1 gene, are associated with the development of prostate cancer in Korean population. keywords : Prostate cancer