Zemskova E Yu, Bordyukov M M, Kovalev A V, Ivanov P L
Department of Molecular-Genetic Expertise, Russian Federal Centre of Forensic Medical Expertise, Ministry of Health of the Russia, Moscow, Russia, 125284.
Department of Molecular-Genetic Expertise, Russian Federal Centre of Forensic Medical Expertise, Ministry of Health of the Russia, Moscow, Russia, 125284; Department of Forensic Medicine, Russian State Medical Academy of Continuous Professional Education, Ministry of Health of the Russia, Moscow, Russia, 125993.
Sud Med Ekspert. 2018;61(2):21-25. doi: 10.17116/sudmed201861221-25.
The authors report the results of the demonstrative study continuing the cycle of interactive discussions pertinent to the possibility of obtaining reliable genetic information from the analysis of burnt bone fragments. Special emphasis is placed on the worthiness of these materials for genotyping of mitochondrial DNA (mtDNA) with the use of the standard analytical methods employed for the purpose of forensic medical expertise to investigate into the length polymorphism of the amplified mtDNA fragments (PAF) by means of sequencing with fluorescent detection. The study has demonstrated that the mtDNA fragments in the state suitable for genotyping can be found only in the preparations from the bone tissue exposed to the 'mild' thermal impact after which the affected bone is virtually indistinguishable from the native one as far as the outward appearance is concerned. In the cases of a more rigorous thermal impact when the bone tissue exhibits well pronounced signs of heat destruction, it should be considered as inherently unsuitable for genotyping of mtDNA. It was shown that chromosomal DNA is inferior to mtDNA in terms of heat resistance. This finding agrees with the currently adopted view, however this advantage of mtDNA is relatively insignificant from the standpoint of genotyping efficiency.
作者报告了一项示范性研究的结果，该研究延续了关于从烧焦骨碎片分析中获取可靠遗传信息可能性的互动讨论周期。特别强调了这些材料对于线粒体DNA（mtDNA）基因分型的价值，即使用法医鉴定中用于通过荧光检测测序来研究扩增的mtDNA片段（PAF）长度多态性的标准分析方法。研究表明，只有在受到“轻度”热影响的骨组织制备物中才能找到适合基因分型的mtDNA片段，在此之后，受影响的骨骼在外观上与天然骨骼几乎没有区别。在热影响更为严重的情况下，当骨组织表现出明显的热破坏迹象时，应认为其本质上不适合进行mtDNA基因分型。结果表明，染色体DNA在耐热性方面不如mtDNA。这一发现与目前所采用的观点一致，然而，从基因分型效率的角度来看，mtDNA的这一优势相对并不显著。
