中国广东汉族群体mtDNA控制区的多态性

目的 探讨线粒体DNA控制区(包括HVⅠ区、HVⅡ区和HVⅢ区)的多态性。方法 采用PCR扩增和末端标记荧光循环测序的方法，对100名广东汉族无关个体进行了序列分析。结果 共观察到147个变异位点，序列变异包括了碱基转换、颠换、插入、缺失等各种类型。其中在HV Ⅰ区(nt16，024～nt16，365)内观察到88个变异位点，91种单倍型，基因多样度为0.9964；在HVⅡ区(nt73～nt340)观察到42个变异位点，67种单倍型，基因多样度为0.9861；在HVⅢ区(nt438～nt574)观察到9个变异位点，15种单倍型，基因多样度为0.8760。联合3个高变区域的序列，可观察到98种单倍型，基因多样度为0.9996。结论 本研究为线粒体DNA在法庭科学中的应用提供了较系统的实验依据。结果还表明，对于mtDNA等单倍型遗传标记，增加其检测范围，可提高该系统的个体识别能力，使其在法庭科学领域充分发挥作用。

The study on the polymorphisms of the mitochondrial DNA control region in Han population in Guangdong province

Objective In order to demonstrate the polymorphisms of the mitochondrial DNA(mtDNA) control region in Guangdong Han population. Methods mtDNAs obtained 100 unrelated individuals were amplified and directly sequenced. Results 147 variable sites were identified, including nucleotide transitions, transversions, insertions and deletions. 88, 42 and 11 polymorphic sites were noted in HVⅠ(ntl6, nt024～nt16, nt365), HVⅡ(nt73～nt340) and HVⅢ(nt438～nt574), respectively. There were 91, 67 and 15 haplotypes detected in HVⅠ, HVⅡ and HVⅢ, respectively. The genetic diversities of HVⅠ、HVⅡ and HVⅢ regions was 0.9964, 0.9861, and 0. 8760, respectively. The randomly matching probability of HVⅠ, HVⅡ and HVⅢ regions were 0.0136, 0.0238 and 0.1328, respectively. When combined the sequence analysis of HVⅠ, HVⅡ and HVⅢ regions, 98 different haplotypes could be found. Amongst these haplotypes, 96 kinds of sequences were observed once, and 2 kinds of sequences were shared by 2 individuals. The combined genetic diversity of the 3 hypervariable regions was 0.9996. The combined matching probability of two unrelated persons having the same sequence was 0. 0104. Conclusion This study provided a systematically experimental basis for forensic casework and demonstrated that sequencing longer mtDNA may raise the power of discrimination.