Polymerase chain reaction–single-strand conformation polymorphism (PCR-SSCP) and PCR–restriction fragment length polymorphism (PCR-RFLP) are two independent methods used in the post-amplification genotyping of DNA variations. Both techniques are used in a wide range of screening applications to characterize single nucleotide polymorphisms (SNPs). The PCR-SSCP enables the identification of a potentially causative unknown SNP that could not be identified by PCR-RFLP. However, because complicated steps are not required to perform PCR-RFLP, it is used in many applications. On the other hand, PCR-RFLP is easier to process in terms of time and handover experience, the detection of a particular unknown SNP by PCR-SSCP has further chances. The simplicity of PCR-RFLP does not mean that it is better than PCR-SSCP. The reason is the limited ability of PCR-RFLP to detect nucleotide variations, which often go undetected because each restriction enzyme (RE) scans only a few recognition sequences, and other sequences are ignored. Furthermore, the efficacy of PCR-SSCP is sometimes hindered by many optimizations and also lack of experience. As PCR-SSCP allows other sequences within an amplicon to be separated and characterized, the choice between PCR-RFLP and PCR-SSCP is largely dependent on the reason for each genotyping experiment. This review provides a useful guide for comparing PCR-RFLP and PCR-SSCP in terms of their concepts, efficiency, ease of use, interpretation, and sensitivity as well as several other parameters. The comparison is extended to the practical applications of both techniques in terms of their utilization in molecular diagnostics and related applications.
13 November 2023 in Journal of Genetic Engineering and Biotechnology
Sanger dideoxy sequencing is vital in clinical analysis due to its accuracy, ability to analyze genetic markers like SNPs and STRs, capability to generate reliable DNA profiles, and its role in resolving complex clinical cases. The precision and robustness of Sanger sequencing contribute significantly to the scientific basis of clinical investigations. Though the reading of chromatograms seems to be a routine step, many errors conducted in PCR may lead to consequent limitations in the readings of AGCT peaks. These errors are possibly associated with improper DNA amplification and its subsequent interpretation of DNA sequencing files, such as noisy peaks, artifacts, and confusion between double-peak technical errors, heterozygosity, and double infection potentials. Thus, it is not feasible to read nucleic acid sequences without giving serious attention to these technical problems. To ensure the accuracy of DNA sequencing outcomes, it is also imperative to detect and rectify technical challenges that may lead to misinterpretation of the DNA sequence, resulting in errors and incongruities in subsequent analyses. This overview sheds light on prominent technical concerns that can emerge prior to and during the interpretation of DNA chromatograms in Sanger sequencing, along with offering strategies to address them effectively. The significance of identifying and tackling these technical limitations during the chromatogram analysis is underscored in this review. Recognizing these concerns can aid in enhancing the quality of downstream analyses for Sanger sequencing results, which holds notable improvement in accuracy, reliability, and ability to provide crucial genetic information in clinical analysis.
17 December 2021 in Computers in Biology and Medicine
Main protease (Mpro) is a critical enzyme in the life cycle of severe acute respiratory syndrome Coronavirus −2 (SARS-CoV-2). Due to its essential role in the maturation of the polyproteins, the necessity to inhibit Mpro is one of the essential means to prevent the outbreak of COVID-19. In this context, this study was conducted on the natural compounds of medicinal plants that are commonly available in the Middle East to find out the most potent one to inhibit Mpro with the best bioavailability and druglikeness properties. A total of 3392 compounds of sixty-six medicinal plants were retrieved from PubChem database and docked against Mpro. Thirty compounds with the highest docking scores with Mpro were chosen for further virtual screening. Variable druglikeness and toxicity potentials of these compounds were evaluated using SwissADME and Protox servers respectively. Out of these virtually screened compounds, artecanin was predicted to exhibit the most favourable druglikeness potentials, accompanied by no predicted hepatoxicity, carcinogenicity, mutagenicity, and cytotoxicity. Molecular dynamics (MD) simulations showed that Mpro-artecanin complex exhibited comparable stability with that observed in the ligand-free Mpro. This study revealed for the first time that artecanin from Laurus nobilis provided a novel static and dynamic inhibition for Mpro with excellent safety, oral bioavailability, and pharmacokinetic profile. This study suggested the ability of artecanin to be used as a potential natural inhibitor that can be used to block or at least counteract the SARS-CoV-2 invasion. Communicated by Ramaswamy H. Sarma