两种包装方式对小体积生物检材DNA检验的影响

目的探讨一种适用于小体积生物物证检材的包装方式。方法选择M4型螺丝钉作为研究对象,经去污消毒处理,通过手握方式转移人体脱落细胞到其表面,对螺丝钉采用两种不同的包装方式(滤纸包裹和悬空固定),经KingFisher Flex自动提取工作站进行DNA提取,从基因座等位基因检出情况、STR分型谱带峰高、均衡性等方面比较两种包装方式对螺丝钉上DNA检出率的影响。结果悬空固定包装螺丝钉实验组获得的STR分型谱带峰高、均衡性等方面均优于滤纸包裹包装实验组,其在基因座检出数量、分型完全相同样本数及有效分型样本数方面也多于滤纸包裹包装实验组。结论为降低微量生物检材DNA二次转移造成的损耗,提高小体积生物检材DNA的检出率,建议对小体积生物检材采用悬空固定方式进行物证包装。

Influence of Two Ways of Packing Size-small Biological Materials on DNA Examination

Objective To explore a method suitable for packing size-small biological materials of evidence.Methods The M4 screws,decontaminated and disinfected,were grasped with hand to have the relevant human epithelial cells transferred onto their surfaces.Two different ways(filter paper wrapping and fixing in suspension)were selected to pack the hand-grasped M4 screws from which DNA was extracted with KingFisher Flex automatic extraction equipment and genotyped of i ts STR profile.The two packing ways were compared of their influence on DNA examination through the detected alleles,STR typing peak height plus equilibrium.Results The packing way of fixing in suspension had resulted in higher STR typing peak height and better equilibrium,having more STR loci detected and more samples revealed of either identical or effective genotyping.Conclusion To reduce the loss resulted from the secondary transfer of DNA harbored with size-small biological materials and improve the detection of involved DNA,the packing way of fixing in suspension is suggested to package the evidential samples of size-small biological materials.