Application of a Repair Enzyme to STR Analysis of Damaged DNA.

Sim, Jeong Eun; Lee, Hwan Young; Yang, Woo Ick; Lee, Seung Hwan; Shin, Kyoung Jin

Original article

Korean Journal of Legal Medicine 2011;35(2):114-119.
Published online November 30, 2011.

Application of a Repair Enzyme to STR Analysis of Damaged DNA.

Jeong Eun Sim, Hwan Young Lee, Woo Ick Yang, Seung Hwan Lee, Kyoung Jin Shin

¹Department of Forensic Medicine and Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea. kjshin@yuhs.ac
²DNA Analysis Laboratory, Division of Forensic DNA, Supreme Prosecutors' Office, Seoul, Korea.

Abstract

DNA found at the scene of a crime is often damaged and degraded to small fragments and remained in low quantity. Therefore, there are some difficulties in forensic STR typing of these DNA samples. In this study, to overcome these limitations as different approach, we applied repairing enzyme to damaged DNA. The efficacy of a repair enzyme system (PreCR Repair Mix) was evaluated by using several types of artificially damaged and naturally damaged DNA. The results showed that autosomal STR amplification produced increased yield in the DNA damaged by UV irradiation, oxidation, or acid/heat, and DNA from dried blood spot and dried saliva spot by treatment of a repair enzyme, but not in DNA extracted from old skeletal remains. In conclusion, a repair enzyme will be efficiently applied to forensic samples which were damaged by UV irradiation, oxidation, and acid/heat.

Key Words: repair enzyme, STR, damaged DNA