A novel microsatellite (STR) marker for forensic identification of big cats in India

India is the home to five of the eight majestic big cats of the world. The three major big cats namely, lion, tiger, and leopard are listed in the Schedule I of the Indian Wildlife Protection Act, 1972. Apart from the severe loss of the habitat, these are continuously facing the danger of extinction mainly due to poaching and hunting for their body parts, which are being greatly valued by apothecaries marketing traditional Chinese medicines. With the advent of polymerase chain reaction (PCR), DNA-based markers have emerged as major tools in the arena of wildlife forensics. Microsatellites (short tandem repeats, STRs) are markers of choice because of their polymorphic and co-dominant nature. These strictly follow the Mendelian inheritance and are highly reproducible. We have identified a new microsatellite (STR) locus Ple 46, which shows amplification in a species-specific manner (size of STR) in all the members of the family felidae studied here. This PCR-based, non-invasive method opens a new avenue to forensic identification of big cats.     

Extra Effort During Memory Retrieval May Be Associated with Increases in Eyewitness Confidence

When testifying in court, witnesses are motivated to try as hard as possible to give an accurate account. This study tested the proposition that extra effort by eyewitnesses during a memory test can lead to higher confidence ratings without any accompanying changes in accuracy. Participant-witnesses answered multiple-choice questions about a classroom visitor who had spoken 5 days earlier. In the high-motivation condition participants could earn prizes based on their memory test performance; in the low-motivation condition there were no special incentives. Although the motivation manipulation did not affect mean witness confidence, the confidence–accuracy and effort–accuracy correlations were substantially smaller in the high-motivation condition than in the low-motivation condition. Furthermore, the confidence ratings for those participants who reported expending high levels of effort in both motivation conditions were significantly higher than the confidence ratings for the low-effort participants, despite the fact that response accuracy did not differ as a function of reported effort. These findings have important implications for understanding how pressures to perform well in the courtroom can affect eyewitness confidence.     

Genetic diversity in four tribal groups of western India: a survey of polymorphism in 15 STR loci and their application in human identification

Genetic diversity at 15 STR loci: 2 pentanucleotide and 13 tetranucleotide STR loci was determined in four highly endogamous tribal groups, viz. Madia-Gond, Mahadeo-Koli, Katkari and Pawara of western India. The distribution of genotypes at studied 15 loci was found in agreement with expected values according to Hardy-Weinberg equilibrium. The combined power of discrimination of 15 loci was calculated as 0.80 while combined power of exclusion was observed as 0.53 among the studied four tribal groups. The study demonstrate very low heterozygosity and low power of exclusion of the loci of Powerplex 16 among the selected groups indicating less informativeness of the studied markers in human identification testing.     

Bite mark documentation and analysis: the forensic 3D/CAD supported photogrammetry approach

Bite mark identification is based on the individuality of a dentition, which is used to match a bite mark to a suspected perpetrator. This matching is based on a tooth-by-tooth and arch-to-arch comparison utilising parameters of size, shape and alignment. The most common method used to analyse bite mark are carried out in 2D space. That means that the 3D information is preserved only two dimensionally with distortions. This paper presents a new 3D documentation, analysis and visualisation approach based on forensic 3D/CAD supported photogrammetry (FPHG) and the use of a 3D surface scanner. Our photogrammetric approach and the used visualisation method is, to the best to our knowledge, the first 3D approach for bite mark analysis in an actual case. The documentation has no distortion artifacts as can be found with standard photography. All the data are documented with a metric 3D measurement, orientation and subsequent analysis in 3D space. Beside the metrical analysis between bite mark and cast, it is possible using our method to utilise the topographical 3D feature of each individual tooth. This means that the 3D features of the biting surfaces and edges of each teeth are respected which is--as shown in our case--very important especially in the front teeth which have the first contact to the skin. Based upon the 3D detailed representation of the cast with the 3D topographic characteristics of the teeth, the interaction with the 3D documented skin can be visualised and analysed on the computer screen.     

Third molar root development in relation to chronological age: a large sample sized retrospective study

The aim of the present investigation, which is a continuation and extension of a previous published pilot study [Forensic Sci. Int. 129 (2002) 110], was to calculate the chronological age of an individual based on the dental developmental stages of third molars (so-called wisdom teeth). The evaluated material consisted of 2513 orthopantomograms (OPG's) of patients all of Belgian Caucasian origin between 15.7 and 23.3 years. The sample of OPG's was scored by two observers who were calibrated for intra- and interobserver reliability by means of kappa statistics. The kappa statistics revealed a strong agreement between the intra- and interobserver measurements. Further statistical analysis was performed in order to obtain multiple regression formulae for dental age calculation with the chronological age as the independent variable and the third molar developmental stages as dependent variables. Both for males and females a significant Pearson correlation coefficient was noticed for contralateral third molars, a smaller less significant one for the antimeres. For the application of the regression formulae one has to take into consideration the gender, the location and number of wisdom teeth. Probabilities for an individual to be older than 18 years were also calculated in case of fully developed wisdom teeth.     

Haplotype diversity in mitochondrial DNA hypervariable regions I and II in three communities of Southern India

The sequence polymorphisms at the mtDNA hypervariable regions I and II (HVR-I and HVR-II) were analyzed in 87 individuals belonging to three religious groups, Hindu, Muslim and Christians of Karnataka (South India). A total of 122 polymorphic sites were observed in the sequenced regions, with HVR-I exhibiting higher variation than HVR-II. The populations exhibited high sequence and nucleotide diversity, alike other studied caste groups of Karnataka.     

The identification of a dismembered human body: a multidisciplinary approach

A criminal case was directed to a multidisciplinary forensic team for identification, concerning a victim whose head, having two gunshot wounds, had been separated by a sharp instrument and was recovered 6 months later. The purpose of this research was to determine the sex and age of the victim for human identification. Primarily, macroscopic examination of the skull, tooth, and DNA analysis was conducted for sex determination. A rough assessment of age was made from the skull based on anthropological findings, however a more definitive result of age estimation was determined utilizing dental morphology. The dental data showed an age range of 32-37 from the mineral examination and the formulation of microscopic measurements. The results obtained from the skull and dental analysis matched with the physical characteristics of the victim's body, the known personal data of this person, and with the superposition of the photos gathered by a formal request. Besides, the result of DNA profiling of the victim showed male gender and direct relationship with the victim's presumed wife and daughter. Generally, research on human identification consists of sex and age determination. The sex characteristics can be precisely proved from DNA tests. However, age can be estimated by skeletal, and dental analysis. In this case the performed sex and age analysis lead the research to the selective matching of the missing person's identity.