MicroRNAs are involved in post-transcriptional down-regulation of gene expression. Variations in miRNA genes can severely affect downstream-regulated genes and their pathways. However, population-specific burden of CNVs on miRNA genes and the complexities created towards the phenotype is not known. From a total of 44109 CNVs investigated from 1715 individuals across 12 populations using high-throughput arrays, 4007 miRNA-CNVs (∼9%) consisting 6542 (∼5%) miRNA genes with a total of 333 (∼5%) singleton miRNA genes were identified. We found miRNA-CNVs across the genomes of individuals showing multiple hits in many targets, co-regulated under the same pathway. This study proposes four mechanisms unraveling the many complexities in miRNA genes, targets and co-regulated miRNA genes towards establishment of phenotypic diversity.

We propose DNA sequencing-based drug resistance detection for TB, which is more accurate than MAS-PCR. Understanding the action of resistant mutations in disrupting the normal drug-protein interaction aids in designing effective drug alternatives.

: A molecular method for diagnosis of drug-resistant Tuberculosis is Multiplex allele-specific PCR (MAS-PCR), which is more time-efficient. Also, understanding the role of mutations when translated to protein, in causing resistance helps better drug designing. Aims: To study MAS-PCR in the detection of drug resistance in comparison to DNA sequencing, and understand the mechanism of interaction of drugs with mutant proteins in Mycobacterium tuberculosis. Methods: Detection of drug-resistant mutations using MAS-PCR and validation through DNA sequencing. MAS-PCR targeted four genes, iniA for the drug Ethambutol, rpsL and rrs for Streptomycin, and gyrA for Fluoroquinolone resistance, respectively. Further, the sequence data was analysed and modelled to study the effect on interaction of the anti-TB drug molecule with the target protein using in silico docking. Results: We identified drug-resistant mutations in four out of 95 isolates with one of them carrying a mutation at codon iniA501, two at gyrA94, and one for both iniA501 and gyrA94 using MAS-PCR. DNA sequencing confirmed drug-resistant mutations in only two isolates, whereas two others had mutation adjacent to the target allele. Molecular docking showed Estimated Free Energy of Binding (ΔG) being higher for Fluoroquinolone binding with GyrA D94V mutant. Both, wild and mutant IniA interact with EMB but had no significant effect on binding energy. Conclusions: DNA sequencing-based drug resistance detection of TB is more accurate than MAS-PCR. Understanding the role of mutations in influencing the drug-protein interaction will help in designing effective drug alternatives.

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Here we report for the first time the SARS-CoV-2 detection in autolysed samples from an exhumed decomposed body post-thirty six days after death. Both naso-oropharyngeal swabs and visceral samples from the lung, intestine, liver, and kidney were collected from the body exhumed post-fifteen days after burial, stored in viral transport medium and in saturated salt solution respectively. Naso-oropharyngeal swabs showed the presence of the SARS-CoV-2 genome as identified by the amplification of viral E, N, RdRP, or ORF1ab genes by RT-PCR. Subsequent examination of tissues reveal the detection of the virus genome in the intestine and liver, while no detection in the kidney and lung. These results signify the genome stability and implicate the virus survival in decomposed swab samples and in tissues and thereafter in storage solution. Further results also indicate spatial distribution of the virus in tissues during the early stage of infection in the subject with no respiratory distress. Considering the presence of cool, humid, and moist location surrounded by the paddy fields, the presence of virus genome might also indicate that SARS-CoV-2 can persist for more than seven days on the surface of dead bodies similar to the Ebola virus, confirming that transmission from deceased subjects is possible for an extended period after death. These results further reaffirm the robustness of the RT-PCR aiding in the detection of viruses or their genome in decomposed samples when other methods of detection could not be useful. Key Words: SARS-CoV-2, Virus survival, Genome stability, Autolysis, RT-PCR.