Differences in tissue distribution of HV2 length heteroplasmy in mitochondrial DNA between mothers and children

Sequence analysis of HV2 in mitochondrial DNA has been performed as a tool for forensic identification, in addition to that of HV1. HV2 contains length heteroplasmy, which shows high variability within an individual or in maternal relatives. In this study, we used cloning analysis and PCR direct sequencing to compare, between mothers and their children, HV2 length heteroplasmic profiles in different tissues. For two mother-child pairs, different types of variant distribution were observed by cloning analysis. In pair 1, length heteroplasmic patterns in most tissues were similar (predominantly 9 and 10Cs variants), but different length heteroplasmic levels, with shifts in predominant genotype, were observed for some hairs in both mother and child. In pair 2, genotype distribution was similar for all tissues, with a predominant 8Cs genotype, but varying in the proportion of minor component. The proportion of one minor length variant (9Cs) in blood from the child was significantly higher than that from the mother, but the proportions of minor components (7 and/or 9Cs) in other tissue samples decreased from mother to child. Moreover, we could confirm that sequence types of PCR products were reflected by the distribution of length variants, which were observed especially in high proportion, in cloning analysis. Our results reveal variable changes in length heteroplasmic level in various tissues between generations. Variability between tissues, especially among hairs, within an individual would result in complicated differences in genotype distribution between maternal generations, and correlate with longer length of Cs for predominant variants.     

Measuring Trade Profile with Granular Product-Level Data

The product composition of bilateral trade encapsulates complex relationships about comparative advantage, global production networks, and domestic politics. Despite the availability of product-level trade data, most researchers rely on either the total volume of trade or certain sets of aggregated products. In this article, we develop a new dynamic clustering method to effectively summarize this massive amount of product-level information. The proposed method classifies a set of dyads into several clusters based on their similarities in trade profile—the product composition of imports and exports—and captures the evolution of the resulting clusters over time. We apply this method to two billion observations of product-level annual trade flows. We show how typical dyadic trade relationships evolve from sparse trade to interindustry trade and then to intra-industry trade. Finally, we illustrate the critical roles of our trade profile measure in international relations research on trade competition.     

1H-NMR of human saliva. An application of NMR spectroscopy in forensic science

1H-NMR was applied to the study of metabolites in human saliva specimens. Acetate, lactate, ethanol, glucose and some other substances were simultaneously identified and quantitated from the 1H-NMR spectra of saliva specimens treated with D2O. These experiments demonstrated the value of 1H-NMR as an analytical method in the field of forensic science and clinical pathology and toxicology.     

Generational change: regional security and Australian engagement with Asia

The rhetoric of US foreign policy since the attack on the World Trade Centre in New York on 11 September 2001, would suggest that there has been a fundamental shift in US foreign relations. This is often summarised as a shift from multilateralism to unilateralism and, in the context of the war on terrorism, concomitantly a shift from geo-economic to geopolitical priorities. The rhetoric of the fight against the ‘axis of evil’, however, may simply cloud underlying continuities in US relations with Asia. Nevertheless the process of coalition-building by the Bush administration in the ‘War on Terrorism’ has impacted on the distance Asian countries have been able to maintain in relation to the United States. The case studies presented in this special issue raise a number of important issues concerning perceptions and the practice of US hegemony and the complex links between leadership and ‘followership’ at the inter-state level. They also draw out the impacts engendered by US–Asia relations on the wider phenomenon of regionalisation in the Asia-Pacific region.     

Mitochondrial DNA and STR typing of matter adhering to an earphone

STR typing and mitochondrial DNA (mtDNA) sequencing were performed on the matter adhering to an earphone found at a crime scene. Experimental studies were carried out using the earphones provided by volunteers. By means of immunohistochemistry, keratinocytes and a portion of nucleated epithelial cells were proven to exist in the contents from the earphones. DNA was extracted by means of the phenol/chloroform method, and the low quantity of extracted DNA was found to be highly degraded. Six STR loci, CSFIPO, TPOX, TH01, F13A01, FESFPS and vWA, were PCR amplified and typed by using two triplex systems (CTT and FFv Multiplexes, Promega, WI), and an amelogenin locus was determined as well. Although partial profiles were observed in some experimental samples, all STR loci could be typed when a considerable amount of high molecular weight DNA was obtained (>0.5 ng/microL). Amplification and sequencing of mtDNA hypervariable region I(15997-16401) and hypervariable region 11(29-408) were all successful. The mitochondrial DNA sequence of the actual case sample, comprising two hypervariable regions and a total of 785 base pairs, showed eight mutations and two insertions with respect to the standard published reference sequence. The genotype was unique in the three published Japanese databases. These results suggest that it is possible to analyze mtDNA from minute amounts of materials and from degraded materials more effectively and routinely in forensic practice.