Evaluation of Nine Non-CODIS MiniSTR Loci to aid Analysis of Degraded DNA

Chung, Ukhee; Lee, Hwan Young; Park, Myung Jin; Yang, Woo Ick; Cho, Sang Ho; Shin, Kyoung Jin

Abstract

For highly degraded DNA samples of forensic casework, new miniSTR PCR systems have been developed to supplement the current CODIS STRs. In the present study, we established the three miniplexes for nine miniSTRs (NC01 : D10S1248, D14S1434 and D22S1045; NC02 : D1S1677, D2S441 and D4S2364; and NC03 : D3S3053, D6S474 and D20S482) which had been previously suggested by Butler group (NIST, Gaitherburg, MD, USA). To evaluate the usefulness of the nine miniSTRs in analysis of degraded DNA, the sensitivity and efficacy of the three miniplexes were determined and then compared with those of the BigMini STR system which consists of six CODIS miniSTRs (TH01, CSF1PO, FGA, TPOX, D7S820, and D21S11). The three miniplexes gave better results in both the sensitivity test and efficiency test in comparison with BigMini. In the sensitivity test using serially diluted standard DNA, most loci in the three miniplexes showed reliable results for samples containing 50 pg of DNA and some even showed good sensitivity for samples containing 30 pg of DNA. Additionally, the three miniplexes generated useful profiles for both enzymatically degraded DNA and 50-year old skeletal remain samples. Among the nine miniSTRs, D4S2364, D3S3053, D14S1434, and D1S1677 produced the most successful DNA profiles for old skeletal remains. These results suggest that new miniSTRs could be useful supplements to the 13 CODIS STRs for forensic analysis of degraded DNA.