@article {46331, title = {Francisella novicida Cas9 interrogates genomic DNA with very high specificity and can be used for mammalian genome editing}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {116}, year = {2019}, month = {OCT}, pages = {20959-20968}, type = {Article}, abstract = {

Genome editing using the CRISPR/Cas9 system has been used to make precise heritable changes in the DNA of organisms. Although the widely used Streptococcus pyogenes Cas9 (SpCas9) and its engineered variants have been efficiently harnessed for numerous gene-editing applications across different platforms, concerns remain regarding their putative off-targeting at multiple loci across the genome. Here we report that Francisella novicida Cas9 (FnCas9) shows a very high specificity of binding to its intended targets and negligible binding to off-target loci. The specificity is determined by its minimal binding affinity with DNA when mismatches to the target single-guide RNA (sgRNA) are present in the sgRNA:DNA heteroduplex. FnCas9 produces staggered cleavage, higher homology-directed repair rates, and very low nonspecific genome editing compared to SpCas9. We demonstrate FnCas9-mediated correction of the sickle cell mutation in patient-derived induced pluripotent stem cells and propose that it can be used for precise therapeutic genome editing for a wide variety of genetic disorders.

}, keywords = {CRISPR Cas9, gene therapy, Genome editing, iPSCs, sickle cell anemia}, issn = {0027-8424}, doi = {10.1073/pnas.1818461116}, author = {Acharya, Sundaram and Mishra, Arpit and Paul, Deepanjan and Ansari, Asgar Hussain and Azhar, Mohd and Kumar, Manoj and Rauthan, Riya and Sharma, Namrata and Aich, Meghali and Sinha, Dipanjali and Sharma, Saumya and Jain, Shivani and Ray, Arjun and Jain, Suman and Ramalingam, Sivaprakash and Maiti, Souvik and Chakraborty, Debojyoti} } @article {47694, title = {FnCas9-based CRISPR diagnostic for rapid and accurate detection of major SARS-CoV-2 variants on a paper strip}, journal = {eLife}, volume = {10}, year = {2021}, month = {JUN }, pages = {e67130}, type = {Article}, abstract = {The COVID-19 pandemic originating in the Wuhan province of China in late 2019 has impacted global health, causing increased mortality among elderly patients and individuals with comorbid conditions. During the passage of the virus through affected populations, it has undergone mutations, some of which have recently been linked with increased viral load and prognostic complexities. Several of these variants are point mutations that are difficult to diagnose using the gold standard quantitative real-time PCR (qRT-PCR) method and necessitates widespread sequencing which is expensive, has long turn-around times, and requires high viral load for calling mutations accurately. Here, we repurpose the high specificity of Francisella novicida Cas9 (FnCas9) to identify mismatches in the target for developing a lateral flow assay that can be successfully adapted for the simultaneous detection of SARS-CoV-2 infection as well as for detecting point mutations in the sequence of the virus obtained from patient samples. We report the detection of the S gene mutation N501Y (present across multiple variant lineages of SARS-CoV-2) within an hour using lateral flow paper strip chemistry. The results were corroborated using deep sequencing on multiple wild-type (n = 37) and mutant (n = 22) virus infected patient samples with a sensitivity of 87\% and specificity of 97\%. The design principle can be rapidly adapted for other mutations (as shown also for E484K and T716I) highlighting the advantages of quick optimization and roll-out of CRISPR diagnostics (CRISPRDx) for disease surveillance even beyond COVID-19. This study was funded by Council for Scientific and Industrial Research, India.}, issn = {2050-084X}, doi = {10.7554/eLife.67130}, author = {Kumar, Manoj and Gulati, Sneha and Ansari, Asgar H. and Phutela, Rhythm and Acharya, Sundaram and Azhar, Mohd and Murthy, Jayaram and Kathpalia, Poorti and Kanakan, Akshay and Maurya, Ranjeet and Vasudevan, Janani Srinivasa and Aparna, S. and Pandey, Rajesh and Maiti, Souvik and Chakraborty, Debojyoti} } @article {47390, title = {Insights from a pan India Sero-epidemiological survey (Phenome-India Cohort) for SARS-CoV2}, journal = {eLife}, volume = {10}, year = {2021}, month = {APR }, pages = {e66537}, type = {Article}, abstract = {

To understand the spread of SARS-CoV2, in August and September 2020, the Council of Scientific and Industrial Research (India) conducted a serosurvey across its constituent laboratories and centers across India. Of 10,427 volunteers, 1058 (10.14\%) tested positive for SARS-CoV2 anti-nucleocapsid (anti-NC) antibodies, 95\% of which had surrogate neutralization activity. Three-fourth of these recalled no symptoms. Repeat serology tests at 3 (n = 607) and 6 (n = 175) months showed stable anti-NC antibodies but declining neutralization activity. Local seropositivity was higher in densely populated cities and was inversely correlated with a 30-day change in regional test positivity rates (TPRs). Regional seropositivity above 10\% was associated with declining TPR. Personal factors associated with higher odds of seropositivity were high-exposure work (odds ratio, 95\% confidence interval, p value: 2.23, 1.92-2.59, \<0.0001), use of public transport (1.79, 1.43-2.24, \<0.0001), not smoking (1.52, 1.16-1.99, 0.0257), non-vegetarian diet (1.67, 1.41-1.99, \<0.0001), and B blood group (1.36, 1.15-1.61, 0.001).

}, issn = {2050-084X}, doi = {10.7554/eLife.66537}, author = {Naushin, Salwa and Sardana, Viren and Ujjainiya, Rajat and Bhatheja, Nitin and Kutum, Rintu and Bhaskar, Akash Kumar and Pradhan, Shalini and Prakash, Satyartha and Khan, Raju and Rawat, Birendra Singh and Tallapaka, Karthik Bharadwaj and Anumalla, Mahesh and Chandak, Giriraj Ratan and Lahiri, Amit and Kar, Susanta and Mulay, Shrikant Ramesh and Mugale, Madhav Nilakanth and Srivastava, Mrigank and Khan, Shaziya and Srivastava, Anjali and Tomar, Bhawana and Veerapandian, Murugan and Venkatachalam, Ganesh and Vijayakumar, Selvamani Raja and Agarwal, Ajay and Gupta, Dinesh and Halami, Prakash M. and Peddha, Muthukumar Serva and Sundaram, Gopinath M. and Veeranna, Ravindra P. and Pal, Anirban and Agarwal, Vinay Kumar and Maurya, Anil Ku and Singh, Ranvijay Kumar and Raman, Ashok Kumar and Anandasadagopan, Suresh Kumar and Karuppanan, Parimala and Venkatesan, Subramanian and Sardana, Harish Kumar and Kothari, Anamika and Jain, Rishabh and Thakur, Anupama and Parihar, Devendra Singh and Saifi, Anas and Kaur, Jasleen and Kumar, Virendra and Mishra, Avinash and Gogeri, Iranna and Rayasam, Geethavani and Singh, Praveen and Chakraborty, Rahul and Chaturvedi, Gaura and Karunakar, Pinreddy and Yadav, Rohit and Singhmar, Sunanda and Singh, Dayanidhi and Sarkar, Sharmistha and Bhattacharya, Purbasha and Acharya, Sundaram and Singh, Vandana and Verma, Shweta and Soni, Drishti and Seth, Surabhi and Vashisht, Sakshi and Thakran, Sarita and Fatima, Firdaus and Singh, Akash Pratap and Sharma, Akanksha and Sharma, Babita and Subramanian, Manikandan and Padwad, Yogendra S. and Hallan, Vipin and Patial, Vikram and Singh, Damanpreet and Tripude, Narendra Vijay and Chakrabarti, Partha and Maity, Sujay Krishna and Ganguly, Dipyaman and Sarkar, Jit and Ramakrishna, Sistla and Kumar, Balthu Narender and Kumar, Kiran A. and Gandhi, Sumit G. and Jamwal, Piyush Singh and Chouhan, Rekha and Jamwal, Vijay Lakshmi and Kapoor, Nitika and Ghosh, Debashish and Thakkar, Ghanshyam and Subudhi, Umakanta and Sen, Pradip and Chaudhury, Saumya Ray and Kumar, Rashmi and Gupta, Pawan and Tuli, Amit and Sharma, Deepak and Ringe, Rajesh P. and Amarnarayan, D. and Kulkarni, Mahesh and Shanmugam, Dhansekaran and Dharne, Mahesh S. and Dastager, Sayed G. and Joshi, Rakesh and Patil, Amita P. and Mahajan, Sachin N. and Khan, Abujunaid Habib and Wagh, Vasudev and Yadav, Rakesh Kumar and Khilari, Ajinkya and Bhadange, Mayuri and Chaurasiya, Arvindkumar H. and Kulsange, Shabda E. and Khairnar, Krishna and Paranjape, Shilpa and Kalita, Jatin and Sastry, Narahari G. and Phukan, Tridip and Manna, Prasenjit and Romi, Wahengbam and Bharali, Pankaj and Ozah, Dibyajyoti and Sahu, Ravi Kumar and Babu, Elapavalooru Vssk and Sukumaran, Rajeev and Nair, Aiswarya R. and Valappil, Prajeesh Kooloth and Puthiyamadam, Anoop and Velayudhanpillai, Adarsh and Chodankar, Kalpana and Damare, Samir and Madhavi, Yennapu and Aggarwal, Ved Varun and Dahiya, Sumit and Agrawal, Anurag and Dash, Debasis and Sengupta, Shantanu} } @article {47346, title = {Rapid and accurate nucleobase detection using FnCas9 and its application in COVID-19 diagnosis}, journal = {Biosensors \& Bioelectronics}, volume = {183}, year = {2021}, month = {JUL }, pages = {113207}, type = {Article}, abstract = {

Rapid detection of DNA/RNA pathogenic sequences or variants through point-of-care diagnostics is valuable for accelerated clinical prognosis, as witnessed during the recent COVID-19 outbreak. Traditional methods relying on qPCR or sequencing are tough to implement with limited resources, necessitating the development of accurate and robust alternative strategies. Here, we report FnCas9 Editor Linked Uniform Detection Assay (FELUDA) that utilizes a direct Cas9 based enzymatic readout for detecting nucleobase and nucleotide sequences without transcleavage of reporter molecules. We also demonstrate that FELUDA is 100\% accurate in detecting single nucleotide variants (SNVs), including heterozygous carriers, and present a simple web-tool JATAYU to aid end-users. FELUDA is semi-quantitative, can adapt to multiple signal detection platforms, and deploy for versatile applications such as molecular diagnosis during infectious disease outbreaks like COVID-19. Employing a lateral flow readout, FELUDA shows 100\% sensitivity and 97\% specificity across all ranges of viral loads in clinical samples within 1hr. In combination with RT-RPA and a smartphone application True Outcome Predicted via Strip Evaluation (TOPSE), we present a prototype for FELUDA for CoV-2 detection closer to home.

}, keywords = {CRISPRDx, FELUDA, FnCas9, LFA, SARS-CoV2, SNV detection}, issn = {0956-5663}, doi = {10.1016/j.bios.2021.113207}, author = {Azhar, Mohd and Phutela, Rhythm and Kumar, Manoj and Ansari, Asgar Hussain and Rauthan, Riya and Gulati, Sneha and Sharma, Namrata and Sinha, Dipanjali and Sharma, Saumya and Singh, Sunaina and Acharya, Sundaram and Sarkar, Sajal and Paul, Deepanjan and Kathpalia, Poorti and Aich, Meghali and Sehgal, Paras and Ranjan, Gyan and Bhoyar, Rahul C. and Singhal, Khushboo and Lad, Harsha and Patra, Pradeep Kumar and Makharia, Govind and Chandak, Giriraj Ratan and Pesala, Bala and Chakraborty, Debojyoti and Maiti, Souvik and Indian CoV2 Genomics Genetic Epide} }