Objective To explore the potential relationship between 6 single nucleotide polymorphisms (SNPs) of mitochondrial DNA (mtDNA) coding region and Parkinson's disease (PD) in northern Chinese population.Methods Samples from 353 patients with PD and 389 control participants,collected in our hospital from April 2010 to November 2015,were genotyped by multiplex polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) techniques.Six SNPs (T4216C within the ND1 gene,A4917G within the ND2 gene,A11084G within the ND4 gene,A12308G within the tRNA gene,A13966G within the ND5 gene,and G15928A within the tRNA gene) in mtDNA were amplified in multiplex PCR systems and subsequently genotyped by digestion with endonucleases.Results An efficient,rapid,and economical way of multiplex genotype SNPs was successfully established.No significant differences were observed in the 6 loci and corresponding haplotypes between PD and control cohorts (P＞0.05).After stratification by gender,however,frequencies of allele 11084G and the haplotype T-A-G-A-A-G in female group with PD were all higher than those in control ones,with significant differences (P＜0.05).Conclusions The 6 SNPs may not be susceptible factors in the northern Chinese population.The A11084G missense mutation might be related to PD in female patients.

The traditional experimental teaching mode of forensic science and biological evidence is mostly confined to experimental operation, which is not capable of cultivating students' comprehensive quality and post competency. Therefore, it is urgent to seek an innovative teaching and training mode. At present, the experimental teaching of forensic science and biological evidence is dominated by teachers. There are some problems, such as insufficient training of students' scientific thinking and innovation ability, single teaching and evaluation model, and disconnection from the practical application. This paper proposes an experimental teaching design scheme of forensic science and biological evidence based on post competency training. The course is implanted in the framework of simulated cases, and the virtual simulation experiment platform and group discussion learning method are used to achieve a training model oriented by social needs and centered on students. In the preliminary study on the students who were trained in this mode of selected sections, we found that, compared with traditional teaching, the time for students to complete the prescribed experimental operation in this teaching mode was shortened by 4 minutes on average, and the average score of theoretical course test case analysis questions was increased by 1.5 points. In conclusion, the instructional design of the experiment teaching forensic science and biological evidence can effectively improve students' post-competency, and it deserves further exploration and application.