The value of DNA material recovered from crime scenes

Abstract:  DNA material is now collected routinely from crime scenes for a wide range of offenses and its timely processing is acknowledged as a key element to its success in solving crime. An analysis of the processing of approximately 1500 samples of DNA material recovered from the property crime offenses of residential burglary, commercial burglary, and theft of motor vehicle in Northamptonshire, U.K. during 2006 identified saliva and cigarette ends as the main sources of DNA recovered (approximately 63% of samples) with blood, cellular DNA, and chewing gum accounting for the remainder. The conversion of these DNA samples into DNA profiles and then into matches with offender profiles held on the U.K. National DNA database is considered in terms of the ease with which Crime Scene Examiners can recover DNA rich samples of different sources, the location of the DNA at the crime scene, and its mobility. A logistical regression of the DNA material recovered has revealed a number of predictors, other than timeliness, that greatly influence its conversion into a DNA profile. The most significant predictor was found to be Crime Scene Examiner accreditation with offense type and DNA sample condition also being relevant. A similar logistical regression of DNA samples profiled that produced a match with an offender on the U.K. National DNA database showed no significance with any of the predictors considered.     

Development of a Real‐Time PCR‐Based Method for Analyzing Semen‐Specific Unmethylated DNA Regions and Methylation Status in Aged Body Fluid Stains

The detection of semen in forensic investigation is considered important evidence of sexual assault. In this study, we report the development of a real‐time polymerase chain reaction‐based method for identifying semen that can simply and rapidly analyze the semen‐specific unmethylated region of the DACT1 gene. Using two fluorescent probes designed for the methylated or unmethylated status, this method could perform quantitative analysis of the methylation status in this region. Furthermore, this method was used to analyze various body fluid samples, including 29‐year‐old semen and blood stains. The results showed that this method can detect almost exclusively semen or nonsemen signals even in highly decomposed samples, while a few semen or nonsemen samples showed slight signals of the other fluorescence probe. Although there is still a need for further analysis such as setting thresholds to analyze unknown samples, this method could be a useful supplementary tool for identifying semen, especially in old stains such as those in cold‐case investigations.     

Swedish Diplomacy in the Asia-Pacific Region

The year 2018 marks the 150th anniversary of the establishment of diplomatic relations between Japan and Sweden. It is believed that the first contact between Sweden and Japan came during the Edo Period and was mediated by the Netherlands. The Treaty of Friendship, Commerce and Navigation between Japan and Sweden, signed in 1868, also came into being thanks to the good offices of the Dutch. This treaty, like many others into which Japan entered at that time, was an “unequal treaty.” As Japan increased its presence in East Asia, this unequal treaty with Sweden was revised in 1911. The world was changing. Sweden and Japan shared a common interest in opposing Russia’s ambitions. Russia in particular was a common threat to the diplomatic posture and security of both Japan and Sweden. These two nations, positioned like bookends on either side of Russia, could be important strategic partners for one another and allies in their relationships with Russia. Considering the current issue of North Korea, Sweden also has the potential to act as a mediator because it maintains diplomatic relations with North Korea. There is reason to believe that the diplomatic relationship between Japan and Sweden will develop further.