Detection of genotype recycling fraud in U.S. immigrants

Abstract: Relationship testing laboratories provide genetic evidence to support or refute claims of kinship between U.S. citizen petitioners and potential immigrant beneficiaries. One female beneficiary presented a male amelogenin type and alleles at 15 autosomal loci that were identical to an alleged brother’s. Laboratory records showed that her alleged father had petitioned to have 15 children emigrate from Ghana. The petitioner’s 15 paternity indices exceeded 10⁵, but the children shared only four short tandem repeat (STR) profiles, suggesting fraudulent reuse of genotypes in this alleged pedigree (AP). To determine the extent of this “genotype recycling,” I examined the laboratory’s 555 APs from Ghana and 532 control APs from Nigeria. Seventeen Ghanaian APs (3.1%) but no Nigerian APs showed genotype recycling. Of 90 tested people in the 17 APs, 56 shared identical STR profiles with others in their AP. Of these 56 people, 10 were petitioners with unexpectedly high parentage indices. Seven of 56 had amelogenin types that disagreed with their declared genders. Database searches for identical multilocus genotypes in allegedly different people would best detect this fraud.     

疱疹病毒UL16基因及其编码蛋白的研究进展

论述了疱疹病毒UL16基因序列的特点、编码蛋白氨基酸序列的特点、基本功能以及与UL11蛋白、UL21蛋白、上皮细胞表面抗原表位的相互作用。表明UL16基因在病毒粒子的装配、囊膜的形成、成熟以及释放中具有重要的作用。     

Enzymatic detection of γ-hydroxybutyrate using aldo-keto reductase 7A2

Gamma-hydroxybutyrate (GHB) is a prescribed medication as well as a drug of abuse. Its detection in various matrices for in-field forensic scientists remains a challenge. We have developed an assay that uses aldo-keto reductase 7A2 (AKR7A2) for the specific determination of GHB in various drinks. AKR7A2 was purified using Ni-affinity chromatography. The Michaelis-Menten constant for the GHB oxidation reaction was 10 mM, and the minimum detection limit was 4 mM. Ethanol was not a substrate for AKR7A2. In a coupled reaction with NADP(+), phenazine methosulfate (PMS), and 2,6-dichlorophenolindophenol, various beverages (orange juice, milk, soda, and numerous alcoholic drinks) containing GHB turned from blue to light yellow. In a second coupled reaction where diaphorase replaced PMS, the presence of GHB also caused the expected change of color in various beers.     

现代税制下的政府收益最大化:概念阐释

本文通过阐述公共产品的最优供给与政府总的净收益之间的联系来界定现代税制下的“政府收益最大化”,指出现代税制下的“政府收益最大化”是政府为了实现公共利益而优化公共产品供给的结果。“公共产品优化供给”的核心指标是纳税人提前支付了公共产品的生产成本后,在公共产品消费过程中不必二次付费。尽管这种“政府收益最大化”并非特定时空政府经济作为的描述,但是它所建立的规范性判断却可以为现代政府的财政决策提供参考或指导,从而有助于政府更好地服从于公共利益的安排。     

牛病毒性腹泻病毒P20及P14蛋白基因的表达及其产物的抗原性分析

将牛病毒性腹泻病毒(bovine viral diarrhea virus,BVDV)p20和p14基因分别亚克隆至原核表达载体pGEX-6p-1和pPROEX-HTb,并转化至相应的宿主菌大肠杆菌BL21(DE3)pLysS和DH5α中表达。P20蛋白在2个宿主中都获得了高效表达;P14蛋白在BL21(DE3)pLysS中表达量较低,而在DH5α中未见表达。对P14蛋白诱导表达过程的监测表明,P14蛋白对大肠杆菌是一种毒性蛋白。用Western-blotting分析未能检测到两种蛋白的反应条带,推测这两种蛋白可能存在构象表位。     

Identifying Diagonal Cutter Marks on Thin Wires Using 3D Imaging

We present work on matching 2‐mm‐thick wires using optical 3D imaging methods. Marks on such small surfaces are difficult to match using a comparison microscope as this 2D imaging method does not provide height data about the sample surface. Moreover, these 2D microscopy images may be affected by illumination. Hence, the reference and investigated sample should be present at the same time. We employed scanning white light interferometry and confocal microscopy to provide quantitative 3D profiles for reliable comparison of samples that are unavailable for simultaneous analysis. We show that 3D profiling offers a solution by allowing illumination‐independent sample comparison. We correctly identified 74 of 80 profiles using consecutive matching striae (CMS) criteria, and we were able to match samples based on profiles measured using different 3D imaging devices. The results suggest that the used methods allow matching cutter marks on thin wires, which has been difficult previously.     

Does the Prior Application of the Field Kit Bullet Hole Testing Kit 3 on a Suspected Bullet Hole Bias the Analysis of Atomic Absorption Spectrophotometry?

Forensic ballistics is the study of bullet trajectory and consists of determining gunshot residue (GSR) to identify bullet holes. Among several highly sensitive methods, atomic absorption spectrophotometry (AAS) is employed to analyze GSR in the laboratory. However, it is sometimes necessary to identify bullet holes immediately at a crime scene. The purpose of this examination was to determine whether the use of the field test Bullet Hole Testing Kit 3 (BTK3) on a suspected bullet hole would influence the outcome of AAS‐analysis: Three commonly encountered firearms (Glock17, Tokarev, and Colt) were fired at skin, wood, and cloth. AAS‐analysis was performed with and without previous BTK3 application. The results clearly indicate that there is no significant interaction on the grounds of BTK3 use (BTK3 vs. no‐BTK3 [kit_nokit] [Pb: p = 0.1309; Sb: p = 0.9111], material*kit_nokit [Pb: p = 0.5960; Sb: p = 0.9930], distance*kit_nokit [Pb: p = 0.4014; Sb: p = 0.9184], and firearm type*kit_nokit [Pb: p = 0.9662; Sb: p = 0.9885]); hence, applying this field kit does not falsify later AAS outcomes.     

False‐Positive Results with Amylase Testing of Citrus Fruits

In a case of robbery in which the criminals passed through the garden adorned with calamondin trees (Citrus madurensis), the investigators found in the grass six calamondin fruits, some undamaged, while others apparently bitten. The fruits were collected and sent to the laboratory for DNA analysis to verify the presence of saliva and robbers' DNA profile. A specific immunochromatographic strip test for saliva confirmed the presence of human salivary α‐amylase, but similar positive results were also observed for intact calamondin and other citrus fruits. Further analysis with a specific automated amylase test confirmed the absence of amylase activity. DNA quantification and typing using a specific forensic kit revealed no human DNA presence in any fruits. This case report demonstrates for the first time the occurrence of false positives when human saliva is sought on citrus fruits.     

眼外伤后GAP-43的时序性表达及法医学意义

生长相关蛋白（GAP-43）是与神经发育、轴突再生、突触重建密切相关的一种快速转运胞膜磷酸蛋白,被认为是神经发育和再生的内在决定因子之一,在多种神经损伤过程中常可检测到GAP-43表达上调。本文综述眼外伤后GAP-43在视觉系统中的表达规律,并初步探讨其法医学意义,希望能为视神经损伤的法医学鉴定提供参考和借鉴。     

钙依赖性蛋白激酶Ⅱδ在脑外伤后皮质中的表达变化

目的：观察钙-钙调素依赖性蛋白激酶Ⅱδ（calcium-calmodulin dependent protein kinaseⅡδ,CaMKⅡδ）在脑损伤后皮质中不同时段的表达变化。方法建立大鼠脑外伤模型,通过Western印迹法和免疫组织化学染色法检测损伤区周围皮质CaMKⅡδ的表达变化。结果 Western印迹法显示,CaMKⅡδ在正常皮质中有表达,损伤后表达上调,在损伤3d达到高峰,并随着损伤时间延长逐渐恢复到正常水平。免疫组织化学结果与Western印迹法结果一致。结论 CaMKⅡδ在脑组织损伤灶及其周围呈现先增高后降低的表达变化,为法医学推断脑外伤后损伤经过时间提供了新的参考指标。