Abstract 4720: Genome-wide copy number variation and breast cancer risk: Preliminary report

Abstract

Abstract Background: DNA copy number variation (CNV) is a common phenomenon in human genome and some CNVs have been associated with susceptibility or resistance to disease. It has been suggested that gene copy number can be elevated in cancer cells. To evaluate potential role of CNV in breast cancer development, we conducted genome-wide association study of CNV in Seoul Breast Cancer Study. Methods: Cases were diagnosed with breast cancer and underwent curative surgery at two teaching hospitals located in Seoul, Korea, between 2001 and 2007 (n=2,386). Control subjects were selected from multi-center based cohort study in 2007 (n=2,386). The Affymetrix SNP assay 6.0 array, which includes 946,000 probes for the detection of copy number variation, was used. Nexus Copy Number version 4.1 was used for detecting CNVs (significance threshold=10−6; minimum number of probes per segment=4), and statistical analysis. After quality control step (i.e., robust variance sample QC), total 2,315 cases and 2,039 controls were compared for the difference of each CNV. In this study, we selected the CNVs that were different between cases and controls by at least 5% (P adjusted for multiple comparison <0.01). Adjacent CNVs were grouped into CNV regions ranging 10 kb to 300 kb. Results: Between case and controls, thirteen CNV regions including chr115q11.2, chr3q26.1, chr6q16.3, chr17q31.1 were significantly different for copy number. We note that those regions include genes such as UGT2B17 (UDP glucuronosyltransferase 2 family, polypeptide B18), OR4C11 (olfactory receptor, family 4, subfamily C, member 11), LRRC37A2 (leucine rich repeat containing 37, member A2), ARL17P1 (ADP-ribosylation factor-like 17 pseudogene 1), LOC644974, and the others. We are planning validation study for the regions by quantitative PCR to verify the association with breast cancer risk found in this study. Conclusion: Our results suggest that common CNVs may be associated with breast cancer in Korean women. However, further variation study is essential to support our observation and underlying biological mechanisms for the associations needs to be elucidated. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4720.