Genotyping-by-sequencing (GBS) is a cost-efficient method which can be useful for SNP marker discovery in a population of interest. GBS is genome reduction sequencing method using restriction enzyme. The quality of DNA is a key factor which could have an influence in downstream analysis. However, there have not been many studies which investigated the impact of DNA degradation and the quality of the data on marker discovery. In this study, GBS data of 6 Hanwoo samples (H1~6) showing differing level of DNA degradation were compared. Re-sequencing pipeline was followed to investigate the impact of DNA degradation on marker discovery. As a result, we found that the quantity and quality of SNPs were not affected in the sample H5 and H6 with moderately degraded DNA. On the other hand, marker discovery was greatly affected in samples with severe DNA degradation (H3 and H4). The findings in this study support that GBS is a robust genotyping method towards moderate DNA degradation.

ABSTRACT
 Ⅰ. 서론
 Ⅱ. 재료 및 방법
  1. Genotype-by-sequencing 을 통한 단편서열 생산
  2. 단편염기서열 자료 정렬을 통한 SNP발굴
 Ⅲ. 결과 및 고찰
  1. Agarose gel 전기영동을 통한 DNA 품질 비교
  2. Genotype-by-sequencing을 통한 단편서열 생산
  3. 참조 유전체 정렬을 통한 SNP발굴
 Ⅳ. 요약
 사사
 Ⅴ. 참고문헌

• 유동안(서울대학교 생물정보학 협동과정, Interdisciplinary Program in Bioinformatics, Seoul National University) | Dong Ahn Yoo
• 김권도(서울대학교 생물정보학 협동과정, (주)조앤김지노믹스, Interdisciplinary Program in Bioinformatics, Seoul National University, C&K Genomics Inc) | Kwondo Kim
• 김덕경((주)조앤김지노믹스, C&K Genomics Inc.) | Duk Kyung Kim
• 조서애((주)조앤김지노믹스, C&K Genomics Inc.) | Seoae Cho Corresponding author