Identification using Hand Remnants at the Mass Casualty Site: Forensic Perspective

Identification is one of the most important aspects of mass disasters. Stature estimation is an essential parameter for identification and is widely used in forensic anthropology, where DNA facility is limited. A hand is most studied part of the upper limb; however, data are scarce concerning particular geographical populations. This study is an effort to provide tangible data for such forensic investigations. It was a prospective, cross-sectional study on 500 medicolegal death cases brought for post-mortem examination. It aimed to estimate stature in the Northwest population using hand and finger measurements of dead persons by mathematical models. A total of seven parameters in hand were used to generate linear and multiple regression equations, correlation coefficients and finger indexes for stature estimation and sex differentiation. The correlation coefficient between stature and all the hand measurements were significant except for the index and middle finger on both sides in females. Bilateral differences were insignificant for hand length and breath, except for the middle finger length in both sexes and length of thumb in females. Multiple regression equations for stature estimation were better than linear regression equations for stature estimation. SEE ranged from 4.31 to 6.26 in males and 4.11 to 5.25 in females. For identification, hand length is the best individual parameter among other hand measurements. The measurement accuracy and practical aspects can be enhanced if we consider cadaveric participants. The multiple regression model approach can give a fair estimate of the stature of the deceased.

Development of a new screening method for faster kinship analyses in mass disasters: a proof of concept study

Kinship analysis in forensics is based on the calculation of the respective kinship indices. However, this calculation is only possible when the subject under identification has been associated with a particular population, whose allele frequency data is available for the particular set of STR markers used in the forensic practices. In the case of mass disasters, where a large number of individuals are to be identified, gathering the population frequency data and calculating the kinship indices can be an intricate process which requires a lot of time and huge resources. The new method of allele matching cut off score (AMCOS) developed in this study is based on the allele sharing approach. This approach simply refers to the number of shared alleles (1 or 2) between the two individuals; also known as identical by state (IBS) alleles which might have been inherited from a recent common ancestor in which the alleles are identical by descendent (IBD). In case of mass disasters, this method can be used to narrow down the number of pairs (dead and alive) to be matched for kinship without using the allele frequency data. The results obtained from this method could further be confirmed by LR based method, which uses the allele frequency data of the respective population of the pairs being tested for kinship. AMCOS method has been tested for its sensitivity, specificity and various other statistical parameters and has shown promising values for the same in various types of kinship analyses. This ascertains the authenticity and potential use of this method in forensic practice but only after its validation in a larger sample size. AMCOS method has been tested on siblings and grandparent-grandchildren by using autosomal and X-STR markers both, as the reference samples from the parents cannot always be available for the identification. The present study also compared the results shown by the autosomal and X-STR markers in siblings and grandparent-grandchildren identification, thereby suggesting the use of better set of markers on the basis of obtained values of various statistical parameters.

Genetic diversity of X-STR markers in Jat Sikh population of Punjab, India and its comparison with other 39 global populations

BACKGROUND

The Jat Sikh population is the largest endogamous group of Punjab, a state in north-west India, and has not yet been explored for genetic polymorphism based on X-STR genetic markers. In India, which is the second most populous country in the world, only two population studies based on X-STR markers have been reported so far.

AIM

To explore the genetic diversity of 12 X chromosomal STR genetic markers in the Jat Sikh population of Punjab and expand the X-STR polymorphism database.

SUBJECTS AND METHODS

In this study, a total of 200 Jat Sikh individuals (100 males and 100 females) residing in Punjab were investigated for 12 X-STR markers using the Investigator Argus X-12 QS Kit.

RESULTS

The highest power of discrimination (PD) in females (PD_f) and males (PD_m) was observed to be 0.965 (DXS10135) and 0.929 (DXS10135 and DXS10148), respectively. DXS10135 was found to be the most polymorphic and discriminating locus among all the studied loci in both males and females with highest values of power of discrimination (PD) and polymorphic information content (PIC) as well.

CONCLUSION

Overall, the studied markers of the Argus 12 X-STR kit provide high polymorphic information which may prove to be an important tool in resolving issues such as missing person identification, incest, immigration disputes, kinship analysis and genealogical studies. The dataset obtained from this study will add to the present database of X-STRs.

Fixed- versus mobile-bearing total knee arthroplasty in Indian patients

PURPOSE

To compare the mid-term clinical outcomes in Indian patients after total knee arthroplasty (TKA) using a fixed- or mobile-bearing prosthesis.

METHODS

120 consecutive patients (50 men and 70 women) aged 55 to 76 (mean, 63) years who had arthritis of the knee with similar deformity and range of motion were randomised to undergo TKA using a fixed- or mobile-bearing prosthesis. Patients with mediolateral instability and infective arthritis were excluded. Knee Society knee and functional scores, range of motion, and the presence of flexion contracture were assessed.

RESULTS

The mean follow-up duration was 3.5 (range, 1-4.6) years. The mid-term outcome of the 2 groups was comparable. One patient with a mobile-bearing prosthesis had recurrent dislocation at postoperative week 2, owing to iatrogenic medial collateral ligament injury.

CONCLUSION

Long-term studies of both functional and radiological outcomes are needed to determine the indications for fixed- versus mobile-bearing prostheses.