Chronicity of high and low level mupirocin resistance in Staphylococcus aureus from 30 Indian hospitals.

Mupirocin is one of the most effective topically used antibiotic for the treatment of dermatitis, nasal carriage, decolonization of methicillin susceptible Staphylococcus aureus and eradication of methicillin resistant Staphylococcus aureus. Extensive use of this antibiotic has resulted in mupirocin resistance in Staphylococcus aureus which is a matter of concern. This study was conducted to evaluate the high and low level of mupirocin resistance in Staphylococcus aureus collected from various Indian hospitals. A total of 600 samples, of which 436 were pus specimens and 164 wound site swabs were collected from 30 Indian hospitals. Disc diffusion and agar dilution methods were used to test mupirocin susceptibility in methicillin resistant Staphylococcus aureus. Out of 600 Staphylococcus aureus isolates, 176 isolates (29.33%) were found to be methicillin resistant Staphylococcus aureus (MRSA). Out of 176 non-duplicate MRSA strains, 138 isolates were found to be mupirocin sensitive, 21 isolates had high level resistance whereas 17 isolates had low level resistance to mupirocin, which contributed 78.41%, 11.93% and 9.66% respectively. Multidrug resistant susceptibility was tested for all the MRSA with Cefuroxime, Cotrimoxazole and Vancomycin antibiotics. All the high and low level resistant strain were subjected to genome screening for mupA ileS gene respectively. mupA gene was found positive in all the high level resistant strain and out of 17 low level resistant strain, 16 strain were found point mutation in V588F of ileS gene. Overall, high rate of mupirocin resistance was found in the studied samples which might be a result of indiscriminate use of mupirocin in the population of studied region. This data emphasizes the urgent need for formulation of a well-defined and regulated guidelines for mupirocin use. Moreover, continuous surveillance is needed for the use of mupirocin and routine test should be performed to detect MRSA in patients and health care personnel to prevent MRSA infections.

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.

An evaluation of inter and intra population structure of Uttar Pradesh, inferred from 24 autosomal STRs.

AIM: The present study was designed to explore the STR diversity and genomic history of the inhabitants of the most populous subdivision of the country. A set of 24 hypervariable autosomal STRs was used to estimate the genetic diversity within the studied population. A panel of 15 autosomal STRs, which is most common in the previously reported data sets, was used to estimate the genetic diversity between the studied population, and obtained unique relations were reported here. METHOD: The genetic diversity and polymorphism among 636 individuals of different ethnic groups, residing in Bareilly, Pilibhit, Shahjahanpur, Gorakhpur, Jhansi, and Varanasi regions of Uttar Pradesh, India, was investigated. This investigation was carried out via 24 autosomal STRs. RESULT: The 24 loci studied showed the highest value of combined power of discrimination (CPD = 1), combined power of exclusion (CPE = 0.99999999985), combined paternity index (CPI = 6.10 × 109) and lowest combined matching probability (CPM = 7.90 × 10-31). CONCLUSION: The studied population showed genetic closeness with the population of Uttarakhand, the Jats of Delhi,the Jat Sikh (Punjab), and the population of Rajasthan. Among the tested loci, SE33 and Penta E were found to be most useful in terms of the highest discrimination power, lowest matching probability, the highest power of exclusion, and highest polymorphism information content for the Uttar Pradesh population .

Genetic portrait of 23 Y-STR loci in the Naga tribes of Nagaland, India.

To explore the genomic diversity and forensic characterization of Naga tribes, Nagaland, haplotypes for 23 Y-STR markers have been analyzed. In this study, 203 unrelated male individuals residing in the Northeast Indian state of Nagaland were selected. A total of 203 unique haplotypes were observed. The value of gene diversity (GD) and discrimination capacity (DC) was observed as 0.999999998927955 and 1 respectively. Forensic interest parameters viz., power of discrimination (PD), polymorphic information content (PIC), and matching probability (PM) were found to be 0.999999998695503, 0.999999976671191, and 1.3 × 10-9 respectively, for the studied population. Inter-population comparison study showed that the Naga tribes were found to have a distinct gene pool which is reflected in the neighbor-joining tree, principle coordinate analysis, and heat map. This is the first genetic study on Naga tribes based on 23 Y-STR markers. The Y chromosomal STR data will be useful for forensic DNA application and will enrich the existing Indian Y-STR database.

Molecular characterization of 23 Y chromosomal STR markers in the Gurjar population of National Capital Region (NCR), India.

In the present study, DNA samples of 202 unrelated male individuals of Gurjar population were evaluated for the molecular diversity at 23 Y chromosomal Y-STR markers. Out of selected individuals, results showed 143 unique haplotypes. Highest degree of gene diversity (GD), polymorphic information content (PIC), and power of discrimination (PD) was observed as 0.7941, 0.7590, and 0.7902, respectively, for the locus DYS385a/b. Haplotype diversity (HD), gene diversity (GD), polymorphic information content (PIC), and power of discrimination (PD) was found to be 0.7079, 0.999999999989, 0.9999999996, and 0.999999999986, respectively, for the studied 23 Y-STR markers. Allele 11 of locus DYS392 was found to be the most frequent allele with the frequency of 0.762. In inter-population relationship, studied population showed genetic relatedness with the population of Jammu and Kashmir, India, and Ladakh, India. The haplotype data of the present study will not only enrich the existing Indian Y-STR data but will also be useful for forensic DNA application.

Efficiency analysis of VersaPlex™ 27PY system in Central Indian Population: First report from Indian population.

In the current scenario, DNA typing is the need of forensic science field due to its ability to provide results in much shorter time. In view of advancement of forensic DNA typing and incensement in the number of STRs markers, Promega offered a new VersaPlex™ 27PY system with 27 loci (23 autosomal STR loci, Amelogenin, DYS391 and two rapidly mutating Y-STR loci (DYS570 and DYS576)). In this study, the efficacy of "23 autosomal STR loci" for paternity testing and personal identification was demonstrated in Indian population. For this, 217 central Indians were tested and all the statistical parameters of forensic and population genetic interest were calculated. In addition, sensitivity of the kit was also tested for forensic casework. During investigation with VersaPlex™ 27PY system, allele 11 at locus TPOX was observed to be most frequent with the highest allelic frequency 0.432. Studied 23 loci showed valuable together with highest value of combined power of discrimination (CPD = 1), combined power of exclusion (CPI = 0.9999999989) and lowest value of combined matching probability (CPM = 7.92x10-28).

Sequence variations, flanking region mutations, and allele frequency at 31 autosomal STRs in the central Indian population by next generation sequencing (NGS).

Capillary electrophoresis-based analysis does not reflect the exact allele number variation at the STR loci due to the non-availability of the data on sequence variation in the repeat region and the SNPs in flanking regions. Herein, this study reports the length-based and sequence-based allelic data of 138 central Indian individuals at 31 autosomal STR loci by NGS. The sequence data at each allele was compared to the reference hg19 sequence. The length-based allelic results were found in concordance with the CE-based results. 20 out of 31 autosomal STR loci showed an increase in the number of alleles by the presence of sequence variation and/or SNPs in the flanking regions. The highest gain in the heterozygosity and allele numbers was observed in D5S2800, D1S1656, D16S539, D5S818, and vWA. rs25768 (A/G) at D5S818 was found to be the most frequent SNP in the studied population. Allele no. 15 of D3S1358, allele no. 19 of D2S1338, and allele no. 22 of D12S391 showed 5 isoalleles each with the same size and with different intervening sequences. Length-based determination of the alleles showed Penta E to be the most useful marker in the central Indian population among 31 STRs studied; however, sequence-based analysis advocated D2S1338 to be the most useful marker in terms of various forensic parameters. Population genetics analysis showed a shared genetic ancestry of the studied population with other Indian populations. This first-ever study to the best of our knowledge on sequence-based STR analysis in the central Indian population is expected to prove the use of NGS in forensic case-work and in forensic DNA laboratories.

Population genetic data of 22 autosomal STR loci for the Scheduled Caste population of Rajasthan India.

AIM: To study the genetic structure of the Scheduled Caste population of Rajasthan and its relationship with Indian and global populations using expanded 20 CODIS STR loci (autosomal) markers. SUBJECTS AND METHODS: Blood samples of 226 healthy, unrelated adult individuals of the Scheduled Caste population of the Indian state of Rajasthan were taken from the routine casework of authors after obtaining written informed consent. Autosomal STR markers included in PowerPlex® Fusion 5 C and GlobalFiler™ PCR amplification kits were used to explore the genetic diversity of the studied population. Amplicons were separated using Genetic Analyser 3500XL as per the recommended protocol. RESULTS: Observed heterozygosity for the studied population ranged from 0.681(CSF1PO) to 0.881 (D1S1656).Combined Discrimination Power and Combined Exclusion Power were observed as 1 and 0.9999999852, respectively. The highest Discrimination Power was observed for the locus D1S1656. In the population comparison test, Nei's Da distance-based Neighbor-Joining (NJ) dendrogram revealed two significant clusters of geographically close Indian and East Asian populations along with a few small groups of outlier populations. CONCLUSION: The matching probability for 20 STR markers was observed as 7.02 × 10-24 and paternity index as 5.55 × 107. These values play a key role in forensic applications.The studied population showed a higher genetic affinity with geographically closer populations than the distant ones. This caste-based population data is expected to play an important role in forensic DNA applications and genetic studies.

Molecular characterization and forensic relevance of the autosomal STRs for the population of North Indian geographical province Himachal Pradesh, India.

Keeping in view the diverse demography of India, present study was undertaken to explore the molecular characterization and forensic relevance of 20 autosomal STRs for the highly diverse population of north Indian state Himachal Pradesh. 724 unrelated individuals from the admixed population of Himachal Pradesh were undertaken for present study and 20 autosomal STRs used to explore genomic diversity of studied population. A total of 270 different alleles along with 13.5 alleles per locus were observed. The allele 8 of the locus TPOX was observed as the most frequent allele. Observed heterozygosity ranged from 0.677 to 0.898, which supported wide range of selection of the unrelated individuals for this study. Combined power of discrimination, power of exclusion, matching probability and paternity index were observed as 1, 0.9999999958, 3.9 × 10-26 and 2.3 × 108 respectively, across the studied loci. In the population differentiation test, studied population showed genetic relatedness with Indian population rather than the populations of West, North and North east countries. Present study deciphered the novel autosomal STR data, which could be useful for the forensic application and population genetic studies.

Genomic polymorphism in tribal population of Tripura: Signifying their closer affinity with the Nepalese and Tibetan populations.

BACKGROUND: India is the second most populous country in the world, which is aligned into various community segments. AIM: To evaluate the genetic diversity of the tribal population of Tripura, we carried out this study. SUBJECTS AND METHODS: 15 autosomal STR markers were used for investigation of genomic diversity, inter- and intra- population relationships among the studied population, and other reported neighbouring tribal and caste populations. RESULTS: Results indicated that the tribals of Tripura share their closer genetic affinity with the Trans-Himalayan (Nepalese, Bhutanese and Tibetan) populations. Locus D18S51 was found as the most discriminatory among all the studied loci with uppermost discrimination power (PD = 0.964) and lowest matching probability (Pm = 0.036) in the study. All the evaluated loci herein are useful, having the maximum value of combined power of discrimination (CPD = 1), combined power of exclusion (CPE = 0.99999746), combined paternity index (CPI = 3 × 105) and combined matching probability (CPm = 2.12 × 1 0 -7). CONCLUSION: Population genetic analysis showed that the studied population has genetic relatedness with the compared Nepalese and Tibetan populations i.e., Kathmandu, Tibet, Newar, and Gorkhas, followed by eastern and central Indian populations.

Revealing genomic history and forensic features of Gurjars from western Uttar Pradesh and National Capital Region Delhi using 23 autosomal STRs.

Here we report the genomic history of Gurjars and framed the useful set of autosomal STRs for Gujjar population. We designed this study with a total number of 215 Gurjars from district Saharanpur (previously known as Gujarat due to presence of many Gujjar zamindars), Moradabad, Bulandshahr, Ghaziabad, Meerut, Noida and NCR Delhi. Locus SE33 was found the most polymorphic and discriminating marker for Gujjar population while locus TPOX is the least. Ancestral information of Gurjars was revealed by comparing the Gujjar's population data with 19 neighbouring populations. In Neighbor Joining (NJ) tree Gurjars were found closer to Gujjars of Jammu region, population of Rajasthan and Uttarkhand, due to the same stock of gene pool.

Forensic characterization and genomic diversity of Assam population viewed from 23 autosomal STRs.

In order to find out the genetic structure and characterize the forensic features of 23 autosomal STRs in the population of Assam, PowerPlex® Fusion 6C amplification kit was employed to genotype 292 unrelated individuals from Assam, India. A total of 79 different alleles were observed across 23 autosomal STRs with the corresponding frequency of alleles, which ranges from 0.002 to 0.406. Selected 23 loci were observed useful together with the highest value of combined discrimination power (CPD = 1), combined exclusion power (CPE = 0.999999999914), combined paternity index (CPI = 3.04 × 109), and all studied loci combined showing the lowest matching probability which is (CPM = 1.29 × 10-29). Additionally, in comparison with neighboring population, Assam population showed genetic closeness with Indian population. The genetic data of the present study will enrich the existing Indian autosomal DNA database and be useful for forensic and genealogical applications.

Genetic diversity and forensic characterization of 15 autosomal microsatellite markers in the North-east Indian Tripuri population.

This study was conducted to explore the genomic diversity and forensic characterization of 15 autosomal microsatellite markers in the East Indian Tripuri population. In the studied population, we observed 158 different alleles with the average 10.53 alleles per locus. The locus D2S1338 (PIC= 0.862) was found to be the most polymorphic wheres locus TPOX (PIC= 0.647) as the least polymorphic, among all the studied loci. The locus FGA was found with the highest number of effective alleles (Nall=19) whereas locus TH01 showed least number of effective alleles (Nall=6). The cumulative values for matching probability (CPm), power of discrimination (CPD), power of exclusion CPE), and paternity index (CPI) were found as 1.94×10-18, 1, 0.999998, and 4.8×105 respectively. The studied population showed genetic closeness with the Gorkha population. In neighbor-joining tree, Tripura population pooled with the population of Nepal and Tibet. The genetic data obtained from the present study will not only enrich the existing autosomal STR database but will also be useful for forensic DNA application and genealogical studies.

Direct PCR amplification from saliva sample using non-direct multiplex STR kits for forensic DNA typing.

Due to its proficiency to provide the most discriminating results for forensic applications, medical research and anthropological studies, multiplex PCR based STR analysis has been established as the most efficient technique in the forensic DNA analysis. Several multiplex amplification kits based on 4, 5 and 6 dyes chemistry are commercially available and used in forensic DNA typing across the globe. These multiplex PCR systems are routinely used for amplification of multiple STR loci (Autosomal, Y and/or X STR's) in the DNA extracted from various biological samples. In the routine forensic DNA testing, DNA profile obtained is compared with the DNA profile of the reference sample, which takes a certain turnaround time and employs costly lab resources. Successive development in forensic DNA typing have resulted in advent of improved multiplex kits which have reduced the effective analysis time, cost and minimized the number of steps required in comparison to conventional forensic DNA typing. Specialized direct amplification compatible multiplex kits are also available nowadays. These kits are relatively costlier but still require few pre-processing steps, which does not make them worth the hefty cost. Herein, this study, we have used non-direct multiplex STR kits to assess their efficacy for direct amplification. In the present study, 103 saliva samples were directly amplified without any pre-treatment of the samples using thirteen non-direct multiplex kits (4 dyes, 5 dyes and 6 dyes chemistry based) for forensic DNA typing. Here, we report a validated direct PCR amplification protocol from the reference saliva samples by omitting DNA extraction and quantification steps, which resulted in 80% reduction of the turnaround time. The developed protocol is cost effective, time efficient and it does not compromise with the quality of DNA profiles. To the best of our knowledge, this is the first report for direct amplification of DNA with the most commonly used non-direct multiplex STR kits without any pre-treatment of the sample. Complete DNA profiles matching all the essential quality parameters were obtained successfully from all the tested samples.

Genomic insight into Y-STR diversity in the population of Odisha, India.

This study evaluated the haplotype diversity of 17 Y chromosomal genetic markers among 202 unrelated males who were randomly selected in the population of Odisha, India. Out of total 196 haplotypes observed in this study, 190 were unique haplotypes. Forensic relevant parameters, viz., gene diversity (GD) and discrimination capacity (DC), were calculated as 0.999999998 and 0.970 respectively, for the studied population. The highest genetic diversity was observed at the locus DYS385a/b (0.9541) and lowest at the locus DYS437 (0.3326) among all the studied Y chromosomal loci. The polymorphic information content (PIC), power of discrimination (PD), and matching probability (PM) was found to be 0.999999965, 0.999999998, and 1.6×10-9 for the tested Y STR loci. The genetic data observed in this study would enrich the existing Y STR data of the Indian population and would also be useful for forensic application.

A study of genomic diversity in populations of Maharashtra, India, inferred from 20 autosomal STR markers.

OBJECTIVE: This study was planned to evaluate the genetic diversity in the admixed and Teli (a Hindu caste) populations of Maharashtra, India using 20 autosomal Short Tandem Repeat (STR) genetic markers. We further investigated the genetic relatedness of the studied populations with other Indian populations. RESULTS: The studied populations showed a wide range of observed heterozygosity viz. 0.690 to 0.918 for the admixed population and 0.696 to 0.942 for the Teli population. This might be due to the multi-directional gene flow. The admixed and Teli populations also showed a high degree polymorphism which ranged from 0.652 to 0.903 and 0.644 to 0.902, respectively. Their combined value of matching probability for all the studied loci was 4.29 × 10-25 and 5.01 × 10-24, respectively. The results of Neighbor-Joining tree and Principal Component Analysis showed that the studied populations clustered with the general populations of Jharkhand, UttarPradesh, Rajasthan and Central Indian States, as well as with the specific populations of Maharashtra (Konkanastha Brahmins) and Tamil Nadu (Kurmans). Overall, the obtained data showed a high degree of forensic efficacy and would be useful for forensic applications as well as genealogical studies.

Forensic characterization and genetic evaluation in the Central Indian population using 27 Y-STRs.

INTRODUCTION: Forensic characterization and genetic evaluation study in the 539 randomly selected unrelated adult healthy individuals belonging to the Central Indian population was undertaken. METHODS: The study was performed using a multiplex of 27 Y-STRs incoporated in Yfiler™ Plus multiplex kit. RESULTS: Out of 539 samples, 6 samples were observed for large deletion and tri-allelic patterns, which were removed from the analysis, and out of 533 samples, a total of 507 haplotypes were found, and out of these haplotypes, 482 unique haplotypes were found in this piece of work. The forensically important parameters, i.e., gene diversity (GD) and discrimination capacity (DC), were found to be 0.669 and 0.951, respectively, for the tested Y STR loci. The genetic data of this study will enrich the Y STR data bank and being used as a potential tool for forensic DNA and various genetic studies.

Genomic polymorphism in North-western Indian population based on autosomal STR's: a population data study.

Genetic diversity indices and forensic parameters at 20 autosomal short tandem repeat (STR) loci were evaluated in 541 unrelated individuals of north-western Indian state Rajasthan. In total, 243 alleles were observed with an average of 12.15 alleles per locus. The most polymorphic and discriminative locus was Penta E with a value of 0.908 and 0.984, respectively. The combined power of exclusion and the combined power of discrimination were found to be 0.999999998 and 1, respectively. Additionally, the genetic relationship of the studied population with the reported Indian as well as global populations was investigated. The studied population showed genetic affinity with the previously reported population of Rajasthan and geographical close population's, i.e., populations of Uttar Pradesh, Madhya Pradesh, and Jharkhand. All the STR loci were found polymorphic, and the select panel of STRs was found suitable for population genetic studies and forensic analysis.

Genetic variation of 20 autosomal STRs in Jats belonging to Delhi, India.

The present study based on 20 autosomal STR polymorphism reveals the genetic diversity of the Jat population of Delhi, India (n = 120). A total of 240 alleles were observed for this study. The allele frequency ranged from 0.004 to 0.508. The studied loci followed the Hardy-Weinberg equilibrium (HWE), and the heterozygosity ranged from 0.658 to 0.908. The locus Penta-E was found the most polymorphic and discriminating in the studied population with the value 0.910 and 0.981, respectively, whereas the locus TPOX was found least polymorphic and discriminating with the value 0.612 and 0.833, respectively. The combined paternity index (CPI) was 1.46 × 109, and the probability of match (CPm) was 2.68 × 10-25 for all 20 autosomal STR loci. The generated data adds to the Indian population database. It will be used for forensic purposes and in other population-based genetic studies.