Liu Peng, Yeung Stephanie H I, Crenshaw Karin A, Crouse Cecelia A, Scherer James R, Mathies Richard A
UCSF/UC Berkeley Joint Graduate Group in Bioengineering, University of California, Berkeley, CA 94720, USA.
Forensic Sci Int Genet. 2008 Sep;2(4):301-9. doi: 10.1016/j.fsigen.2008.03.009. Epub 2008 May 20.
An integrated lab-on-a-chip system has been developed and successfully utilized for real-time forensic short tandem repeat (STR) analysis. The microdevice comprises a 160-nL polymerase chain reaction reactor with an on-chip heater and a temperature sensor for thermal cycling, microvalves for fluidic manipulation, a co-injector for sizing standard injection, and a 7-cm-long separation channel for capillary electrophoretic analysis. A 9-plex autosomal STR typing system consisting of amelogenin and eight combined DNA index system (CODIS) core STR loci has been constructed and optimized for this real-time human identification study. Reproducible STR profiles of control DNA samples are obtained in 2h and 30min with <or=0.8bp allele typing accuracy. The minimal amount of DNA required for a complete DNA profile is 100 copies. To critically evaluate the capabilities of our portable microsystem as well as its compatibility with crime scene investigation processes, real-time STR analyses were carried out at a mock crime scene prepared by the Palm Beach County Sheriff's Office (PBSO). Blood stain sample collection, DNA extraction, and STR analyses on the portable microsystem were conducted in the field, and a successful "mock" CODIS hit was generated on the suspect's sample within 6h. This demonstration of on-site STR analysis establishes the feasibility of real-time DNA typing to identify the contributor of probative biological evidence at a crime scene and for real-time human identification.
一种集成的芯片实验室系统已被开发出来，并成功用于实时法医短串联重复序列（STR）分析。该微型设备包括一个160纳升的聚合酶链反应反应器，带有片上加热器和用于热循环的温度传感器、用于流体操作的微阀、用于标准大小注射的共注射装置以及一个7厘米长的用于毛细管电泳分析的分离通道。针对这项实时人类身份鉴定研究，构建并优化了一个由牙釉蛋白和八个联合DNA索引系统（CODIS）核心STR位点组成的9重常染色体STR分型系统。对照DNA样本可在2小时30分钟内获得可重复的STR图谱，等位基因分型准确率≤0.8碱基对。完整DNA图谱所需的最小DNA量为100个拷贝。为了严格评估我们便携式微系统的能力及其与犯罪现场调查流程的兼容性，在棕榈滩县警长办公室（PBSO）准备的模拟犯罪现场进行了实时STR分析。在现场对便携式微系统进行了血迹样本采集、DNA提取和STR分析，并在6小时内对嫌疑人样本成功生成了“模拟”CODIS匹配结果。这种现场STR分析的演示证明了实时DNA分型在识别犯罪现场有证明力的生物证据提供者以及进行实时人类身份鉴定方面的可行性。
