2011-08-012024-05-14https://scholars.lib.ntu.edu.tw/handle/123456789/656168摘要：矽藻是存在自然水域中具有矽殼的單細胞生物，其種屬分佈隨環境不同而異，因此，鑑定矽藻可以研判法醫案件是否與水有關，而矽藻種屬的定量分析可以研判法醫案件可能發生的地點。在國外，矽藻鑑定是疑似溺死案件之許多必須篩檢的重要證據之一；在國內則尚未成為研判依據，甚是可惜。為讓矽藻鑑定成為法醫實驗室或刑事實驗室鑑定的重要項目，本研究將建立矽藻DNA 鑑定的快速篩檢模式，以利實驗室採用。本研究第一年將建立多藻種之16S 與18S rDNA 之SSCP 快速鑑定方法，設計矽藻之共通引子複製出矽藻DNA，再以選殖法定出複製出的矽藻種屬，並預估培養30 種矽藻，再配合培養出的純種矽藻進行驗證，建立資料庫，以建立矽藻DNA 快速鑑定方法。第二年將建立以ITS DNA 特異片段進行矽藻種屬之快速鑑定方法，尋找共通引子複製出矽藻DNA，以長度差異與序列差異，分別建立快速的鑑定方法，並預估再培養30 種矽藻合計60 種矽藻，再以此純種矽藻進行驗證，建立資料庫。第三年將結合前兩年建立的兩個方法與資料庫，針對30 個疑似溺死案件的法醫檢體蝶竇水進行分析，並評估相關水域的矽藻，檢驗其地理性特徵的顯著性情形，以建立精確的地理性特徵的研判方法。<br> Abstract: Diatoms are single cells with silica frustule in nature waters. The species distributionsare variable on the different environment. Therefore diatom identification can reveal whethera forensic case is related to water or not. Diatom distribution can provide a possible site of theprimary crime scene. In many forensic medicine laboratories from foreign countries, diatomscreening is one of major work. In Taiwan, there is still at its infant stage. In order toproviding forensic lab a feasible method on diatom identification, this study will establish fastscreening methods based on DNA profiling in the first year. The diatom’s specific DNAfragments of 16S and 18S rDNA will be amplified with universal primers and cloned. Thesefragments will be confirmed by cultured diatoms and analysed by SSCP method. We expectdatabase of the specific 16S and 18S DNA fragments of 30 cultured diatoms will beestablished. In the second year, the ITS DNA fragments will be analyzed for fast screening.The universal primers will be designed for amplification. Sequence and size variations amongspecies will be analyzed. Another 30 diatom species will be isolated. The database of 16S,18S and ITS DNA sequences of 60 cultured diatom species will be established. The study ofthe third year will focus on the forensic specimens. At least 30 diatom DNA from sphenoidfluid of suspect drowning and relevant waters will be extracted and tested with the establishedmethods. Further evaluation of geographic features will be established.法醫學矽藻DNA鑑定溺死Forensic medicinediatomDNA identificationdrowning