Genetic polymorphism revealed by 13 tetrameric and 2 pentameric STR loci in four Mongoloid tribal population

The short tandem repeat allelic profiles at to 15 autosomal polymorphic loci were analyzed in four tribal populations of Mizoram (India). The analysis was performed on 354 unrelated healthy individuals belonging to Mongoloid races. All the samples were subjected to sex test (Amelogenin marker) besides the STR typing and in all instances; it has shown no deviation from expectation. The allele frequencies for all the analyzed loci in the studied populations are within expected range in comparison to the populations from same racial background. No significant deviation from the Hardy-Weinberg Equilibrium was observed for all the populations. In no cases the observed heterozygosity is less than that of expected values and it varied from 0.978 (Penta E) to as low as 0.425 (THO1). The discriminatory power and exclusion probability values for all the analyzed markers are significantly high and thus reveal high forensic significance. There is no evidence for association of alleles among the 15 studied loci. This allele frequency data will be useful for human identity testing in Mizo population.     

Response of short tandem repeat systems to temperature and sizing methods

In capillary gel electrophoresis (CE), changing run conditions such as temperature can result in minor variations in the size determination of an allele. These effects are caused by secondary structure differences that can occur between the amplified sample and the internal standard. The type of method chosen to generate the sizing curve in STR analysis can influence the relationship between estimated allele size and temperature. To better understand the effects of temperature and sizing method on the reproducibility of DNA migration, two fluorescently labeled allelic ladders, CTTv and Y-PLEX 6 were analyzed using the ABI Prism 310 Genetic Analyzer. The default method on the Genetic Analyzer utilizes an electrophoretic temperature of 60 degrees C and a Local Southern method to generate a sizing curve from the fragment migration times of the internal lane standard. In this work, electrophoresis was conducted at 35-70 degrees C using the commercially available POP 4 buffer at pH 8 and two sizing methods, Global Southern and Local Southern, were compared. The slopes of the regression line between estimated allele size and temperature, using either sizing method, were measured in order to demonstrate the temperature sensitivity of migration time and the importance of the operator-chosen method. Our results indicate that the Global Southern method is a better choice in situations where temperature fluctuations can occur. In addition, the temperature dependence of the DNA size estimates using the POP 4 system were compared to results obtained using an experimental buffer consisting of 3% hydroxyethylcellulose at pH 11. These results demonstrate that secondary structure effects are minimized at an elevated pH, increasing the precision of size estimates obtained.     

Genetic profile of the Ecuadorian Mestizo population (Ecuador-South America) by using the Power Plex 16 System Kit

Allele frequency data for the 15 STR systems and Amelogenine were determined in a population sample of healthy Mestizo unrelated individuals. All loci met Hardy-Weinberg expectations and the high discrimination power of combined system showed the forensic efficiency of these genetic markers. There is a lack of information on Ecuadorian population from a genetic point of view and therefore no previous publications on the distribution of STRs on Mestizos is available. Mestizos are descendents of Spanish and Amerindian people, however, significant differences were found between the former and the populations from Spanish peninsula, that have been analyzed for these genetic markers.     

Population data on the AmpFlSTR SGM plus PCR amplification kit in Germans and Austrians

Allele frequencies for the short tandem repeat loci D3S1358, VWA, D16S539, D2S1338, D8S1179, D21S11, D18S51, D19S433, THO1 and FGA were determined in 231 German and 100 Austrian unrelated Caucasoids using the AmpFlSTR SGM plus kit (Applied Biosystems). All loci met Hardy-Weinberg expectations. In 212 meioses per locus, one mutation event for D19S433 was observed.     

High prevalence of 6-acetylmorphine in morphine-positive oral fluid specimens

Identification of 6-acetylmorphine, a specific metabolite of heroin, is considered to be definitive evidence of heroin use. Although 6-acetylmorphine has been identified in oral fluid following controlled heroin administration, no prevalence data is available for oral fluid specimens collected in the workplace. We evaluated the prevalence of positive test results for 6-acetylmorphine in 77,218 oral fluid specimens collected over a 10-month period (January-October 2001) from private workplace testing programs. Specimens were analyzed by Intercept immunoassay (cutoff concentration=30 ng/ml) and confirmed by GC-MS-MS (cutoff concentrations=30 ng/ml for morphine and codeine, and 3 ng/ml for 6-acetylmorphine). Only morphine-positive oral fluid specimens were tested by GC-MS-MS for 6-acetylmorphine. A total of 48 confirmed positive morphine results were identified. An additional 107 specimens were confirmed for codeine only. Of the 48 morphine-positive specimens, 32 (66.7%) specimens were positive for 6-acetylmorphine. Mean concentrations (+/-S.E.M.) of morphine, 6-acetylmorphine and codeine in the 32 specimens were 755+/-201, 416+/-168 and 196+/-36 ng/ml, respectively. Concentrations of 6-acetylmorphine in oral fluid ranged from 3 to 4095 ng/ml. The mean ratio (+/-S.E.M.) of 6-acetylmorphine/morphine was 0.33+/-0.06. It is suggested that, based on controlled dose studies of heroin administration, ratios >1 of 6-acetylmorphine/morphine in oral fluid are consistent with heroin use within the last hour before specimen collection. The confirmation of 6-acetylmorphine in 66.7% of morphine-positive oral fluid specimens indicates that oral fluid testing for opioids may offer advantages over urine in workplace drug testing programs and in testing drugged drivers for recent heroin use.     

Canadian students join struggle for access to treatment

Canadian students have joined the struggle for global access to treatment. This article describes initiatives at McGill University and the University of Toronto.     

Deep incisional neck injuries caused by an electric knife

Electric knives, due to the double blades swinging in opposite directions, have a high injury potential. Tissues such as skin can be cut smoothly without cutting motion and with only little pressure. Authors report on the case of a woman of 47 years who cut herself deeply on both sides of her neck with an electric knife, slightly carving a notch into the larynx and a cervical vertebra and opening large blood vessels. With respect to the extent of injuries the capacity to act had to be questioned. However, considering the absence of venous air embolism and the peculiarity of the tool it had to be assumed that the capacity to act lasted for a short time.     

Conceiling the cadaver in masonry and cement

Encasing with concrete and/or bricks are relatively rare forms of hiding or disposing of a body; criminologically, cases of this kind are often treated as "matters involving a missing person" at first. The article describes the circumstances and findings of 2 cases in which bodies were encased with concrete. Under the aspects of reconstruction it is of importance that bodies may be preserved quite well in concrete, which allows not only identification of the victim but also determination of the cause of death even after a prolonged post-mortem interval, the more so as occasionally tools used for committing the offense are also encased together with the body.