Population dynamics and genetic isolation in the Central Himalayan region: insights from Sikkim population, India.

India's rich diversity encompasses individuals from varied geographical, cultural, and ethnic backgrounds. In the field of population genetics, comprehending the genetic diversity across distinct populations plays a crucial role. This study presents significant findings from genetic data obtained from the Sikkimese population of India. Autosomal markers were crucial for evaluating forensic parameters, with a combined paternity index of 1 × 109. Notably, Penta E emerged as a distinguishing marker for individual identification in the Sikkim population. Fst genetic distance values revealed insights into genetic isolation among different groups, enhancing our understanding of population dynamics in the central Himalayan region. The NJ-based phylogenetic tree highlighted close genetic relationships, of the Sikkim population with the Nepalese population surrounding neighbouring Himalayan populations providing glimpses into common ancestry. In summary, this study contributes valuable data to population genetics and underscores the importance of genetic variation in comprehending population dynamics and forensic applications.

Evaluation of genetic polymorphisms at 21 autosomal STR loci in Ramgharia Sikh population of Punjab, India.

BACKGROUND: STR (Short Tandem Repeat) markers are highly polymorphic markers, which are widely used in forensics DNA analysis and aid to ascertain unique genotype profiles of individuals and determine the genetic diversity of the given population. AIM: In the present study, an attempt has been made to evaluate the population genetic diversity of the Ramgharia Sikh population of Punjab, India, using 21 autosomal STR loci (D3S1358, vWA, D16S539, CSF1PO, TPOX, D8S1179, D21S11, D18S51, D2S441, D19S433, TH01, FGA, D22S1045, D5S818, D13S317, D7S820, SE33, D10S1248, D1S1656, D12S391, and D2S1338) to augment the emerging forensic database related to the indigenous population of India. SUBJECTS AND METHODS: For generation of the database, 200 (blood on FTA card) samples were obtained from genetically unrelated Ramgharia Sikhs residing in the state of Punjab. Twenty-one autosomal STR markers were analysed using the Globalfiler® PCR amplification kit. RESULTS: With the help of various statistical tools, a total of 232 alleles were observed and 11.048 ± 1.284 (mean ± standard deviation) alleles per locus were recorded. No locus deviated from Hardy Weinberg Equilibrium. SE33 locus was found to be the most polymorphic and exhibited the highest discrimination power, that is, 0.99. Moreover, results further indicated that Ramgharia Sikhs of Punjab showed a high affinity with Bhils of Madhya Pradesh (India). Thus, the studied population showed genetic proximity with the geographically close populations of India and showed significant genetic variations with distant populations, which was evident from the UPGMA tree and Principal Component Analysis plot. CONCLUSION: Overall, the 21 autosomal STRs were found to be polymorphic in the Ramgharia population and suitable for forensic casework and studies on population genetics.

Key genetic and forensic attributes of Uttarakhand population of India.

The present study aimed to investigate the genetic and forensic attributes of Uttarakhand population based on 20 autosomal STR loci implemented in PowerPlex® 21 System. Results unveiled 219 alleles ranging from 6 (TH01, TPOX) to 20 (Penta E). Forensic analysis revealed locus Penta E as the most polymorphic and discriminative loci, whereas genetic analysis indicated presence of higher heterozygosity within population. Phylogenetic analysis indicated higher genetic affinity of Uttarakhand population with the neighbouring Himachal Pradesh population. Overall, the study indicates that the PowerPlex® 21 System is suitable for genetic and forensic analysis in Uttarakhand population.

Genetic polymorphism of 20 autosomal short tandem repeats (STRs) in Himachal Pradesh population, India.

Genetic diversity indices and forensic parameters at 20 autosomal short tandem repeat (STR) loci were evaluated in 233 unrelated individuals of Himachal Pradesh, India. In total, 255 alleles were observed with an average of 11.25 ± 0.88 alleles per locus. None of the loci deviated from Hardy Weinberg Equilibrium. The most polymorphic and discriminative locus was Penta E. The combined power of exclusion and the combined power of discrimination were found to be 0.99 and 1. Additionally, the genetic relationship of the Himachal Pradesh population with the populations of the neighboring state was also investigated. All the STR loci were found polymorphic, and the select panel of STRs was found suitable for population genetic studies and forensic analysis.

DNA profiling in India: Addressing issues of sample preservation, databasing, marker selection, & statistical approaches.

DNA technology is the gold standard with respect to the identification of individuals from biological evidence. The technology offers the convenience of a universally similar approach and methodology for analysis across the globe. However, the technology has not realised its full potential in India due to the lack of a DNA database and lacunae in sample collection and preservation from the scene of crime and victims (especially those of sexual assault). Further, statistical interpretation of DNA results is non-existent in the majority of cases. Though the latest technologies and developments in the field of DNA analysis are being adopted and implemented,very little has been enacted practically to improve optimise sample collection and preservation. This article discusses current casework scenarios that highlight the pitfalls and ambiguous areas in the field of DNA analysis, especially with respect DNA databases, sampling, andstatistical approaches to genetic data analysis. Possible solutions and mitigation measures are suggested.

Genetic Diversity of Autosomal STR Markers in the Brahmin Population of Rajasthan and Haryana: Significance in Population and Forensic Genetics.

The aim of the study is to evaluate the suitability of STRs for molecular characterization and forensic applications in unrelated Brahmins of Rajasthan and Haryana states, India. Materials and Methods: A total of 203 male DNA samples from various districts of Haryana (n=104) and Rajasthan (n=99) were genotyped using the GlobalFiler® PCR Amplification Kit. Allelic frequencies and different forensic parameters like PD, PE, PIC, PM, Ho, He, UHe, and TPI were calculated with different software. Results: More than 200 alleles were present in both populations, ranging from 6.0 to 35.2 and SE33 was the most polymorphic marker. The combined power of discrimination was 1. To know the relatedness with other Indian Brahmin populations, the UPGMA dendrogram and principal component analysis plot were visualized to show that both populations are close to each other and in nearby Saraswat Brahmins of Himachal Pradesh. This study showed a genetic relationship and forensic examination in the Haryana and Rajasthan Brahmin populations and various ethno-linguistically diverse populations of India. Conclusion: The results imply that the highly polymorphic 21 autosomal STR loci might be applied for individuals' forensic identification and parentage testing. This study also suggests that the kit having both autosomal and Y-STR markers is appropriate for a better understanding of the genetic and forensic examination in the Brahmin population of Haryana and Rajasthan.

Applicability of human-specific STR systems, GlobalFiler™ PCR Amplification Kit, Investigator 24plex QS Kit, and PowerPlex® Fusion 6C in chimpanzee (Pan troglodytes).

OBJECTIVES: Human identification systems based on STRs are widely used in human population genetics and forensic analysis. This study aimed to validate the cross-reactivity of three widely known human-specific STR identification systems i.e. GlobalFiler™ PCR Amplification Kit, Investigator 24plex QS Kit, and PowerPlex® Fusion 6C in chimpanzee. RESULTS: The present study revealed the successful amplification of 18 loci using GlobalFiler™ PCR Amplification Kit, 18 loci using Investigator 24plex QS Kit, and 20 loci using PowerPlex® Fusion 6C system. The marker Amelogenin (AMEL) showed differential allele size between male and female revealing the gender identity of chimpanzees and thus validates their application concerning forensic examination, population estimation, and genetic analysis.

Genetic evidence of shared ancestry among diverse ethno-linguistic human populations of Himachal Pradesh.

In Indian montane system, human populations often exhibit an unparallel social organization where inter-caste marriages are still not common. This attribute affects the demography and population genetic structure of the resident populations. Further, human populations residing in the mountains in India are poorly studied for their genetic make-up and allele distribution patterns. In the present study, we genotyped 594 unrelated individuals using PowerPlex® 21 System (Promega, USA) from eight different populations belonging to 12 districts of Himachal Pradesh which differed in ethnicity, language, geography and social organization. Altogether, we obtained 1415 alleles with a mean of 8.84 ± 0.26 alleles per locus and 0.80 mean observed heterozygosity. Locus Penta E showed the highest combined power of discrimination and was found most informative for forensic purposes. Interestingly, phylogenetic analysis grouped the populations of Rajputs, Scheduled castes and Brahmins into one cluster, which indicated a deep genetic admixture in the ancestral populations. This study documents the first-ever report on the population genetic assignment of various castes in Himachal Pradesh and unveils the facts of cryptic gene flow among the diverse castes in the northern hilly state of India. Our results showed a genetic relationship among the various ethno-linguistically diverse populations of India.