粒線體MTATP6及MTATP8基因序列變化在粒線體DNA型別次分類與人別鑑定應用之評估

Abstract

人類粒線體DNA因為具有母系遺傳、高突變率、細胞內數量很多等特性，可應用於法醫學微量檢體作人身鑑別。粒線體DNA非轉譯區hypervariable region 1 (HV1)及hypervariable region 2 (HV2)，為粒線體DNA變異頻率最高的區域，常被用來作為法醫學人身鑑別的工具，為了區分擁有相同HV1及HV2序列的無親屬關係之任二人，本研究蒐集台灣無親屬關係的167個漢人個案，分析其MTATP6與MTATP8基因序列多型性，並與同一個檢體之D-loop、MTCYB、MTCOI基因序列比較，評估應用這些片段在法醫人身鑑別及型別分類的能力。在167個DNA檢體中，842個核苷酸序列中有62個序列點位與rCRS不同，共53種haplotypes，haplotype diversity為0.8982 +/- 0.0168、nucleotide diversity為0.002751 +/- 0.001675、Random match probability(RMP)為10.72%、Power of discrimination(PD)為0.8928。在單倍群型別分析中，分析D-loop、MTATP6及MTATP8、MTCOI、MTCYB之倆倆合併序列，有24%(25/102)的檢體合併D-loop以外之序列分析後其haplogroup有改變。所有檢體的單倍群以M haplogroup為最多(28.4%，29/102)，其中又以M7最多，佔18.6%(19/102)，B haplogroup次之(22.5%，23/102)，其中以B4最多，佔17.6%(18/102)。本研究利用台灣漢人MTATP6與MTATP8基因序列的多型性建立haplotype frequency，可能可作為輔助目前常用的HV1及HV2序列分析的人身鑑別。在法醫人類學上，除了應用D-loop分類haplogroup外，MTATP6及MTATP8可能有助於建立haplogroup的次型別分類，使haplogroup的區分更為詳細，作為研究人類族群來源、遷移之依據。

The characteristics of human mitochondrial DNA (mtDNA), such as maternal inheritance, high mutation rate, and high copy number allow mtDNA to be applied to forensic trace samples for human identification. The hypervariable region 1 (HV1) and the hypervariable region 2 (HV2), with high frequency of variation, are often used as a tool for forensic human identification. In order to distinguish between two unrelated persons with the same HV1 and HV2 sequence, we collected DNA samples of 167 unrelated Taiwanese Han. The polymorphisms of the MTATP6 and MTATP8 genes were analyzed. Evaluation of the usefulness of the mtDNA region polymorphisms including D-loop, MTCYB, MTCOI, MTATP6 and MTATP8 for forensic human identification and haplogroup subclassification was performed. In 167 DNA samples, there were 62 positions that varied form the rCRS with a total of 53 haplotypes found in the 842 nucleotide sequence of MTATP6 and MTATP8 genes. The haplotypes diversity, the nucleotide diversity and the random match probability (RMP) were 0.8982 +/- 0.0168, 002751 +/- 0.001675 and 10.72% respectively. In the the haplogroup analysis of D-loop, MTATP6, MTATP8, MTCOI, and MTCYB sequence, 24% of the sample changed their haplogroup subclassifiction with additional sequence polymorphism outside D-loop. The M haplogroup was the most common haplogroup(28.4%), among which the M7 was the most common subhaplogroup, accounting for 18.6%. The second common haplogroup was B haplogroup (22.5%), among which B4 was the most common (17.6%). In this thesis, polymorphisms of MTATP6 and MTATP8 in Taiwanese Han were analyzed. These polymorphisms may serve as an auxiliary of HV1 and HV2 sequence analysis for human identification. In forensic anthropology, in addition to the D-loop haplogroup, MTATP6 and MTATP8 may help to further subclassify the haplogroups for establishing the maternal lineage and migration of Taiwanese Han population.