Development of a Tetraplex PCR Assay for CYP2D6 Genotyping in Degraded DNA Samples

CYP2D6 polymorphism analysis is gaining increasing interest in forensic pharmacogenetics. Nevertheless, DNA recovered from forensic samples could be of poor quality and not suitable for long polymerase chain reaction required to type CYP2D6 gene prior to SNaPshot minisequencing analysis performed to define alleles with different enzymatic activity. We developed and validated following the guidelines of the Scientific Working Group on DNA Analysis Methods a tetraplex PCR yielding four amplicons of 597, 803, 1142, and 1659 bp encompassing the entire CYP2D6 gene to analyze eleven SNP positions by SNaPshot minisequencing. Concordance, sensitivity, and specificity were assessed. The method, applied to thirty‐two forensic samples failed to amplify with long PCR, allowed the amplification of CYP2D6 gene in 62.5% of degraded samples. The new tetraplex PCR appears a suitable method for CYP2D6 analysis in forensic pharmacogenetics.     

汉族人群DXS9898基因座的遗传多态性

目的研究汉族群体DXS9898基因座的遗传多态性,为法科学应用提供基础数据。方法应用PCR及PAG电泳技术,对成都地区汉族群体199名女性无关个体及97名男性无关个体进行群体遗传学调查。结果共检出6个等位基因,片段大小为189～214bp,其基因型分布符合Hardy-Weinberg平衡。家系调查证实等位基因的传递遵循孟德尔遗传规律。女性样本杂合度为0.5930;男、女性样本个人识别能力(Dp)分别为0.5667、0.9420;父-母-女三联体鉴定的非父排除率(PE)为0.5862。结论DXS9898基因座在法科学个人识别及女性小孩的亲权鉴定中具有较高的实用价值。     

An innovative transfer DNA experimental design and qPCR assay: Protocol and pilot study

Forensic “touch” DNA samples are low-quantity samples that are recovered from surfaces that have been touched by single or multiple individuals. These samples can include DNA from primary contributors who directly touched the surface, as well as secondary contributors whose DNA was transferred to the surface through an intermediary. It is difficult to determine the type of transfer, or how often and under what conditions DNA transfer occurs. In this paper, we present an innovative protocol that combines (1) a paired male and female transfer DNA experimental design in which the presence of male DNA indicates secondary transfer and (2) a cost-effective quantitative PCR (qPCR) assay of a sex-specific region in the Amelogenin gene to detect male and female DNA. We evaluate the ability of the Amelogenin qPCR assay to detect low concentrations of male and female DNA in mixed samples. We also test experimental DNA samples using our transfer DNA protocol to differentiate primary and secondary DNA transfer. Male DNA was detected in the majority of known mixed samples, even in samples with 4× more female DNA—this result demonstrates the ability to detect low concentrations of male DNA and the presence of secondary transfer DNA in our experimental design. Primary DNA transfer was detected in 100% of our experimental trials and secondary DNA transfer was detected in 37.5% of trials. Our innovative protocol mimics realistic case scenarios to establish rates of primary and secondary DNA transfer in an inexpensive and simplified manner.     

猪流行性腹泻病毒SYBRⅠ实时荧光定量RT-PCR检测方法的建立

参考GenBank上登录的猪流行性腹泻病毒(PEDV)株的ORF3基因序列保守型片段设计特异性引物,建立了检测PEDV的SYBR GreenⅠ荧光定量RT-PCR方法。在4.32×102～4.22×107copies范围内,它有很好的线性关系,其扩增相关系数为0.999,扩增效率为99%,扩增产物的熔解曲线只出现1个特异峰,无引物二聚体,熔解温度为82.23℃±0.19℃。它对传染性胃肠炎病毒、猪轮状病毒、猪细小病毒、猪流感病毒、猪繁殖与呼吸综合征病毒、伪狂犬病病毒、猪瘟病毒均检测不到荧光信号,表明其特异性强。该方法的组内变异系数为0.05%～0.87%,组间变异系数为0.32%～1.24%,重复性好。结果表明,建立的SYBRⅠ实时荧光定量RT-PCR为PEDV早期感染的诊断及定量分析提供了新的方法。     

美国疫苗伤害补偿计划及其对我国的启示

上世纪80年代,美国为了应对疫苗供应危机,颁布了《国家儿童疫苗伤害法》,1988年开始实行疫苗伤害补偿计划,经过几年的努力,初步实现了国会的双重立法目标。我国应借鉴美国的经验,明确立法目标,由国家制定统一的补偿标准,不断扩大补偿范围,制定更具操作性的规定,进一步完善我国的疫苗伤害补偿制度。     

SUPERVISION REGIMES,RISK, AND OFFICIAL REACTIONS TO PAROLEE DEVIANCE*

Parolee deviance has emerged as a central issue in policy debates about crime and punishment in American society as well as in scholarship on “mass incarceration.” Although the prevailing approach to studying parolees conceives of parole violations as outcomes of individual propensities toward criminal behavior (i.e., criminogenic risk), we consider how indicators of individual risk and characteristics of formal social control systems combine to account for reported parole violations. Using data on California parolees, we examine the effects of parolees’ personal characteristics, their criminal histories, and the social organization of supervision on parole violations. We advance the notion of a “supervision regime”—a legal and organizational structure that shapes the detection and reporting of parolee deviance. Three components of a supervision regime are explored: 1) the intensity of supervision, 2) the capacity of the regime to detect parolee deviance, and 3) the tolerance of parole officials for parolee deviance. We find that personal characteristics and offense histories are predictive of parole violations. However, we also find that introducing supervision factors reduces the effects of offense history variables on violation risk, suggesting that the violation risks of serious, violent, and sexual offenders are partially explainable through the heightened supervision to which they are subject. In addition, we find that supervision intensity and tolerance are generally predictive of violation risk. Capacity effects are present but weak. We conclude with a discussion of how the supervision regimes concept illuminates the gap between macro‐ and micro‐analyses of social control.     

大鼠死后脑、心肌和肾组织β-actin mRNA的降解与早期死亡时间的关系

目的 研究SD大鼠脑、心肌和肾组织细胞内β-actin mRNA的降解与早期死亡时间的关系,为早期死亡时间的推断寻找新的指标.方法 大鼠处死后置于20℃的环境中,分别于死后不同时间点提取脑、心肌、肾的总RNA,采用实时荧光定量RT-PCR方法检测总RNA中β-actin mRNA的水平(Ct值),分析死后经过时间与Ct...     

Analysis of Dopamine D2 Receptor (DRD2) Gene Polymorphisms in Cannabinoid Addicts*

Abstract: The gene encoding the dopamine D2 receptor (DRD2) has been suggested as a candidate gene for substance dependence. In this study, the possible association between Taq1A and Taq1B DRD2 polymorphisms and cannabinoid dependence was investigated. One hundred and twelve cannabinoid addicted and 130 healthy control subjects were included in this study. The Taq1A and Taq1B genotypes were determined in all subjects by polymerase chain reaction. For each polymorphism (A or B), the subjects were categorized into three groups according to their genotype, that is, the subjects with alleles A1/A1, A1/A2, A2/A2; B1/B1, B1/B2, and B2/B2. A significant association was found between Taq1A gene polymorphism and cannabinoid addicts compared to the control subjects. This finding suggests that polymorphism of the Taq1A, but not the Taq1B, may be associated with the susceptibility to cannabinoid dependence. Further clinical studies are required to be carried out for confirmation and evaluation of these findings.     

应用RNA分析技术推断现场血痕形成时间

目的检测血痕中β-actin mRNA和18S rRNA在人体死后8～15d期间的表达残留,为推断血痕形成时间寻找新的客观依据。方法在上述时段内每天抽提血痕总RNA,利用实时定量RT-PCR技术监测18S rRNA和β-actin mRNA的扩增状况并对产物进行定量分析,通过检测18S rRNA与β-actin mRNA含量在各个时间点的变化趋势来推测血痕形成时间。结果死后8～15 d时段内18S rRNA与β-actinmRNA量的比值呈明显升高趋势,显示出两种不同类型RNA降解的时间差异性。结论一定时段内18SrRNA与β-actin mRNA量的相对变化,可作为推测血痕形成时间的参考指标。     

Molecular Identification of Three Indian Snake Species Using Simple PCR–RFLP Method*

Abstract: Three endangered Indian snake species, Python molurus, Naja naja, and Xenochrophis piscator are known to be significantly involved in illegal trade. Effective authentication of species is required to curb this illegal trade. In the absence of morphological features, molecular identification techniques hold promise to address the issue of species identification. We present an effective PCR–restriction fragment length polymorphism method for easy identification of the three endangered snake species, Python molurus, Naja naja, and Xenochrophis piscator. A 431‐bp amplicon from cytochrome b gene was amplified using novel snake‐specific primers following restriction digestion with enzymes Mbo II and Fok I. The species‐specific reference fragment patterns were obtained for the target species, which enabled successful identification of even highly degraded shed skin sample confirming the utility of the technique in case of poor‐quality DNA. The assay could be effectively used for forensic authentication of three Indian snake species and would help strengthen conservation efforts.