DNA Analysis Research Articles

ISOLATION AND ANALYSIS OF NATIVE DNA AND RNA FROM ROOTS OF RUBBER-PRODUCING SPECIES SCORZONERA TAU-SAGHYZ LIPSCH. ET G.G. BOSSE

Scorzonera tau-saghyz Lipsch. et G.G.Bosse, is endemic species, growing in South Kazakhstan and alternative (to Hevea brasilians) source of natural rubber, related to the Asteraceae Family. Natural rubber (NR) is an indispensable raw material for the production of different products for medicine, automotive and aviation industries. The introduction of tau-saghyz into the culture will make it possible to obtain NC not only in Kazakhstan, but also on the territory of the countries of the Northern latitudes. At the growing phases of ontogenesis of tau-saghyz (April-June) latex is actively synthesized in the leaves and transported to the roots. In our experiments it was necessary to conduct molecular genetic studies of the selected forms of tau-saghyz with high rubber concentration. In this regard, it became necessary to isolate and analyze native DNA and RNA from dry roots. Samples with the highest rubber content were used for DNA extraction. The main problem in the isolation of DNA from the dry roots of tau-saghyz is the significant content of natural rubber. In this research the following commercial kits were used: 1) DNeasy Plant Mini Kit (Qiagene); 2) GenElute Plant Genomic DNA Miniprep Kit (Sigma); 3) NucleoSpin® Plant II / Midi / Maxi kit (Macherey-Nagel). Further DNA isolation was carried out in accordance with the kit manufacturer's protocol. Quantitative DNA analysis was performed using both UV spectrophotometry (Nanodrop) and fluorometric analysis (Qubit) method. DNA extracted by the 2 kit (Sigma) was further purified by precipitation with ethanol and demonstrates satisfactory quality. Functional analysis of isolated DNA samples was performed both by restriction analysis and by DNA amplification. It is worth to mention that for reaction primers that are characteristic of gene AACT (ACETOACETYL-COA TRANSFERASE) Cucumis melo were used. This enzyme catalyzes the first reaction of biosynthesis in the mevalonate pathway, which the final product is IDP (isopentenyl diphosphate). The cis-prenyltransferase (CPT) enzyme catalyzes the biosynthesis of rubber by the sequential addition of IDP to the terminal group of the initiating allylic pyrophosphate (APP). As a result of PCR analysis a putative 1200 bp AAST gene for tau-saghyz was identified. In this study two methods of RNA isolation were chosen: 1. A method widely used for plants of the Cucurbitaceae family; 2. A method approved for plants with a high content of polyphenols. The RNA isolation was carried out as described in the relevant protocols with minor modifications (Verwoerd TC, Dekker BMM, Hoekema A (1989) A small-scale procedure for the rapid isolation of plant RNAs. Nucleic Acids Res 17:2362). The final precipitates were dissolved in 50 µl of water pretreated with diethylpyrocarbonate. Quantitative analysis of RNA was carried out using UV spectrophotometry (Nanodrop). Functional analysis of extracted RNA samples was conducted by cDNA synthesis with usage of reverse transcriptase Superscript IV with the following amplification in PCR. In this reaction the primers specific for CPT gene of Taraxacum kok-saghyz were used. The prospective CPT gene was excised from the gel, purified and cloned into the pJET vector. In the further research it is planned to perform its sequencing and comparison with the CPT gene of Taraxacum kok-saghyz and Hevea brasiliensis.

Developing a Machine-Learning 'Smart' PCR Thermocycler, Part 1: Construction of a Theoretical Framework.

The use of PCR is widespread in biological fields. Some fields, such as forensic biology, push PCR to its limits as DNA profiling may be required in short timeframes, may be produced from minute amounts of starting material, and may be required to perform in the presence of inhibitory compounds. Due to the extreme high-throughput of samples using PCR in forensic science, any small improvement in the ability of PCR to address these challenges can have dramatic effects for the community. At least part of the improvement in PCR performance could potentially come by altering PCR cycling conditions. These alterations could be general, in that they are applied to all samples, or they could be tailored to individual samples for maximum targeted effect. Further to this, there may be the ability to respond in real time to the conditions of PCR for a sample and make cycling parameters change on the fly. Such a goal would require both a means to track the conditions of the PCR in real time, and the knowledge of how cycling parameters should be altered, given the current conditions. In Part 1 of our work, we carry out the theoretical groundwork for the ambitious goal of creating a smart PCR system that can respond appropriately to features within individual samples in real time. We approach this task using an open qPCR instrument to provide real-time feedback and machine learning to identify what a successful PCR 'looks like' at different stages of the process. We describe the fundamental steps to set up a real-time feedback system, devise a method of controlling PCR cycling conditions from cycle to cycle, and to develop a system of defining PCR goals, scoring the performance of the system towards achieving those goals. We then present three proof-of-concept studies that prove the feasibility of this overall method. In a later Part 2 of our work, we demonstrate the performance of the theory outlined in this paper on a large-scale PCR cycling condition alteration experiment. The aim is to utilise machine learning so that throughout the process of PCR automatic adjustments can be made to best alter cycling conditions towards a user-defined goal. The realisation of smart PCR systems will have large-scale ramifications for biological fields that utilise PCR.

Methodological assessment for efficient collection of Schistosoma mansoni environmental DNA and improved schistosomiasis surveillance in tropical wetlands

Schistosomiasis, caused by trematodes of genus Schistosoma, is among the most seriously neglected tropical diseases. Although rapid surveillance of risk areas for Schistosoma transmission is vital to control schistosomiasis, the habitat and infection status of this parasite are difficult to assess. Environmental DNA (eDNA) analysis, involving the detection of extra-organismal DNA in water samples, facilitates cost-efficient and sensitive biomonitoring of aquatic environments and is a promising tool to identify Schistosoma habitat and infection risk areas. However, in tropical wetlands, highly turbid water causes filter clogging, thereby decreasing the filtration volume and increasing the risk of false negatives. Therefore, in this study, we aimed to conduct laboratory experiments and field surveys in Lake Victoria, Mbita, to determine the appropriate filter pore size for S. mansoni eDNA collection in terms of particle size and filtration volume. In the laboratory experiment, aquarium water was sequentially filtered using different pore size filters. Targeting >3 µm size fraction was found to be sufficient to capture S. mansoni eDNA particles, regardless of their life cycle stage (egg, miracidia, and cercaria). In the field surveys, GF/D (2.7 µm nominal pore size) filter yielded 2.5-times the filtration volume obtained with a smaller pore size filter and pre-filtration methods under the same time constraints. Moreover, a site-occupancy model was applied to the field detection results to estimate S. mansoni eDNA occurrence and detection probabilities and assess the number of water samples and PCR replicates necessary for efficient eDNA detection. Overall, this study reveals an effective method for S. mansoni eDNA detection in turbid water, facilitating the rapid and sensitive monitoring of its distribution and cost-effective identification of schistosomiasis transmission risk areas.

Molecular diagnostics of familial hypercholesterolemia in Russia: yesterday, today and tomorrow

Familial hypercholesterolemia is a severe hereditary disease leading to the development of atherosclerosis and its complications in the form of angina pectoris, myocardial infarction, cerebral stroke, or even leading to sudden death. Since the description of the disease, the concept of it has undergone significant evolution. First, it became clear that the prevalence of this disease was significantly higher than originally thought (1:300 for heterozygous familial hypercholesterolemia and not as 1:500 as estimated earlier). Secondly, it has been established that it is not based on the pathology of the low-density lipoprotein receptor gene alone, but includes at least four monogenic forms (defects of the APOB, PCSK9, ARH genes) and may also have a multigenic nature. Thirdly, with the development of DNA analysis methods from the initially available Southern hybridization to next generation DNA sequencing, the exceptional molecular heterogeneity of familial hypercholesterolemia became obvious and, accordingly, the need to establish national spectra of mutations leading to the development of familial hypercholesterolemia was established. Researchers have moved from characterizing individual mutations to creating national registries and databases. Finally, research into the genetics of familial hypercholesterolemia has led to the emergence of new classes of cholesterol-lowering drugs. In Russia, molecular diagnostics of familial hypercholesterolemia has also undergone significant changes since the beginning of the study of familial hypercholesterolemia in 1987 and to the present, consideration of these changes formed the basis of this review.

A comprehensive evaluation of Cell Elution Method (CEM) for forensic DNA analysis from smoked cigarettes

Cigarette stubs are commonly encountered trace DNA samples at crime scenes. Standard laboratory practice typically involves direct lysis of the stub for DNA extraction, leading to the co-extraction of DNA-degrading and inhibiting constituents from smoke and tobacco. This process can result in lower-quality DNA profiles. There has been limited focus on developing specific sample processing techniques that minimize these degrading agents and inhibitors before DNA extraction, which could significantly enhance the quality of DNA profiles. This study evaluates a previously established Cell Elution Method (CEM) against the conventional Direct Lysis Method (DLM) for DNA extraction from cigarette stubs. DNA quantity, quality, and subsequent STR profiles were assessed in 80 smoked cigarette stubs, comprising both flavoured and unflavoured types. While CEM exhibited comparable DNA yield from both flavoured (0.17 ng) and unflavoured (0.19 ng) cigarettes, DLM showed significant variability in average DNA yield for unflavoured (0.05 ng) and for flavoured (0.25 ng) cigarettes. Notably, CEM-treated samples demonstrated lower Degradation Index (DI) values compared to DLM-treated ones for both the types of cigarettes. Consequently, STR profiling success rates were higher with CEM, with 95 % of flavoured and 55 % of unflavoured samples yielding informative profiles, compared to 80 % and 0 %, respectively, for DLM. In unflavoured stubs, Amelogenin marker amplification was achieved in 35 % of CEM-treated samples, significantly outperforming the 5 % success rate with DLM. Additionally, CEM resulted in higher average allele recovery rates for both flavoured (58.98 %) and unflavoured (33.41 %) samples compared to DLM. These findings indicate that CEM outperforms DLM in producing higher-quality DNA profiles from cigarette stubs. Thus, CEM can be a choice of method for processing cigarette stub prior to DNA extraction.

A consultation and work-up diagnosis protocol for a multicancer early detection test: a case series study.

The emergence of multicancer early detection (MCED) tests holds promise for improving early cancer detection and public health outcomes. However, positive MCED test results require confirmation through recommended cancer diagnostic imaging modalities. To address these challenges, we have developed a consultation and work-up protocol for definitive diagnostic results post MCED testing, named SPOT-MAS. Developed through circulating tumor DNA (ctDNA) analysis and in line with professional guidelines and advisory board consensus, this protocol standardizes information to aid general practitioners in accessing, interpreting and managing SPOT-MAS results. Clinical effectiveness is demonstrated through a series of identified cancer cases. Our research indicates that the protocol could empower healthcare professionals to confidently interpret circulating tumor DNA test results for 5 common types of cancer, thereby facilitating the clinical integration of MCED tests.

Identification of diagnostic candidates in Mendelian disorders using an RNA sequencing-centric approach

BackgroundRNA sequencing (RNA-seq) is increasingly being used as a complementary tool to DNA sequencing in diagnostics where DNA analysis has been uninformative. RNA-seq enables the identification of aberrant splicing and aberrant gene expression, improving the interpretation of variants of unknown significance (VUSs), and provides the opportunity to scan the transcriptome for aberrant splicing and expression in relevant genes that may be the cause of a patient’s phenotype. This work aims to investigate the feasibility of generating new diagnostic candidates in patients without a previously reported VUS using an RNA-seq-centric approach.MethodsWe systematically assessed the transcriptomic profiles of 86 patients with suspected Mendelian disorders, 38 of whom had no candidate sequence variant, using RNA from blood samples. Each VUS was visually inspected to search for splicing abnormalities. Once aberrant splicing was identified in cases with VUS, multiple open-source alternative splicing tools were used to investigate if they would identify what was observed in IGV. Expression outliers were detected using OUTRIDER. Diagnoses in cases without a VUS were explored using two separate strategies.ResultsRNA-seq allowed us to assess 71% of VUSs, detecting aberrant splicing in 14/48 patients with a VUS. We identified four new diagnoses by detecting novel aberrant splicing events in patients with no candidate sequence variants from prior DNA testing (n = 32) or where the candidate VUS did not affect splicing (n = 23). An additional diagnosis was made through the detection of skewed X-inactivation.ConclusionThis work demonstrates the utility of an RNA-centric approach in identifying novel diagnoses in patients without candidate VUSs. It underscores the utility of blood-based RNA analysis in improving diagnostic yields and highlights optimal approaches for such analyses.

Establishment and biological characteristics of a human buccal mucosa squamous cell carcinoma cell line SCC117

Objective: To establish a human buccal mucosa squamous cell carcinoma (BMSCC) cell line SCC117 in China, analyze and identify its basic biological characteristics. Methods: A 59-year-old Chinese male patient with BMSCC in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology in January 2011 was included in this study, his surgical specimens were primary cultured in vitro by improved tissue block culture method. The BMSCC cell line SCC117 was established after continuous passage and stable growth. The morphological characteristics of the cells were observed by light and electron microscope, and their basic biological characteristics were analyzed by growth curve, chromosome karyotype and xenotransplantation tumorigenicity in nude mice experiment. The expressions of cytokeratin (CK14), tumor-related proteins retinoblastoma tumor suppressor protein (RB), P53, E-cadherin, P21, phosphatase and tensin homolog deleted on chromosome ten (PTEN) were detected by immunohistochemical and human papilloma virus (HPV) were tested by PCR. SCC117 was identified by short tandem repeat (STR) analysis of genomic DNA. Results: SCC117, a human BMSCC cell line, had been continuously subcultured in vitro for more than 150 generations. The cells grew in polygonal mosaic and lost contact inhibition, the typical desmosomes and tensional fibrils were observed by electron microscope, and CK14 was positive by immunohistochemistry. The doubling time was 40.16 h, the chromosome mode of the cell line was concentrated between 67 and 69, hypo-triploid. All 4 nude mice inoculated with SCC117 cells developed tumors, indicating that the SCC117 cell line had the ability of xenogeneic tumorigenesis. The histopathological type of the transplanted tumor in nude mice was consistent with that of the primary tumor tissue, both of which were squamous cell carcinoma. The immunohistochemical results showed that in both human primary tumor and the transplanted tumor tissue in nude mice, RB, P53, and E-cadherin were all positive, P21 was weakly positive, while PTEN was negative. SCC117 was tested negative for the presence of HPV. STR sequence analysis showed that SCC117 cell line originated from primary tumor tissue and was not cross-contaminated by other cell lines. Conclusions: The human BMSCC cell line SCC117 was successfully established in China, which could provide a new experimental model for the study of oral SCC without HPV infection, especially BMSCC.

Characterization of blaOXA-232 carrying carbapenem-resistant Klebsiella pneumoniae (CRKP) & their expression profiles under selective carbapenem pressure: An in-depth study from India.

Background & objectives OXA-232 is a five amino acid substitution variant of OXA-48 and is reported in carbapenem-resistant Klebsiella pneumoniae (CRKP), which is associated with nosocomial infections among immunocompromised patients in the intensive care unit. This study aimed to characterise blaOXA-232 in CRKP of clinical origin and investigate its transcriptional response against sub-inhibitory levels of carbapenems. Methods CRKP was isolated from blood (pathogens) and stool cultures (colonisers) of neonates and was characterized for blaOXA-232. Co-existing resistance determinants were investigated in blaOXA-232 positive isolates, followed by horizontal gene transferability assay and PCR-based replicon typing (PBRT). Cloning of blaOXA-232 was performed, and expression of blaOXA-232 in the isolates and their clones under sub-inhibitory concentrations of carbapenems was checked via RT-PCR. Mobile genetic elements associated with blaOXA-232 were investigated, followed by DNA fingerprinting through enterobacterial repetitive intergenic consensus (ERIC) PCR. Results blaOXA-232 with co-carriage of extended-spectrum beta-lactamases (ESBLs), sulphonamides and quinolones were identified in seven CRPK isolates recovered from blood samples of neonates. Transformation and cloning of blaOXA-232 was successful. The sub-inhibitory concentration of carbapenems induces elevated expression of this resistant determinant. ISEcp1 was associated with blaOXA-232 in the upstream region within two haplotypes of CRKP isolates of clinical origin. Interpretation & conclusions Selective carbapenem pressure resulted in higher expression of this gene, which could account for treatment failure. With frequent reports of occurrence among clinical isolates, monitoring and further investigation of this novel variant are necessary to understand its transmission dynamics and to thwart its further dissemination.

Shotgun DNA sequencing for human identification: Dynamic SNP selection and likelihood ratio calculations accounting for errors

Shotgun sequencing is a DNA analysis method that potentially determines the nucleotide sequence of every DNA fragment in a sample, unlike PCR-based genotyping methods that is widely used in forensic genetics and targets predefined short tandem repeats (STRs) or predefined single nucleotide polymorphisms (SNPs). Shotgun DNA sequencing is particularly useful for highly degraded low-quality DNA samples, such as ancient samples or those from crime scenes. Here, we developed a statistical model for human identification using shotgun sequencing data and developed formulas for calculating the evidential weight as a likelihood ratio (LR). The model uses a dynamic set of binary SNP loci and takes the error rate from shotgun sequencing into consideration in a probabilistic manner. To our knowledge, the method is the first to make this possible. Results from replicated shotgun sequencing of buccal swabs (high-quality samples) and hair samples (low-quality samples) were arranged in a genotype-call confusion matrix to estimate the calling error probability by maximum likelihood and Bayesian inference. Different genotype quality filters may be applied to account for genotyping errors. An error probability of zero resulted in the commonly used LR formula for the weight of evidence. Error probabilities above zero reduced the LR contribution of matching genotypes and increased the LR in the case of a mismatch between the genotypes of the trace and the person of interest. In the latter scenario, the LR increased from zero (occurring when the error probability was zero) to low positive values, which allow for the possibility that the mismatch may be due to genotyping errors. We developed an open-source R package, wgsLR, which implements the method, including estimation of the calling error probability and calculation of LR values. The R package includes all formulas used in this paper and the functionalities to generate the formulas.

Performance comparison of a previously validated microhaplotype panel and a forensic STR panel for DNA mixture analysis

Short Tandem Repeats (STRs) are the most widespread markers in forensic genetics. However, STR stutter peaks can mask alleles from a minor contributor when analysing mixtures, hindering the interpretation of complex profiles. In this study we compared the performance of a previously described panel of microhaplotypes (MHs), an alternative type of forensic marker, against a standard STR kit. The parameters evaluated included: capability of determining the minimum number of contributors in the mixture; percentages of allele drop-outs and drop-ins; retrieval of alleles belonging to the minor contributor, and estimation of likelihood ratio (LR) values. In addition, the capacity of EuroForMix software to estimate each donor’s percentage of contribution was tested, as well as the impact on results when using manually, or automatically prepared libraries. The MH panel showed better performance than STRs for the detection of 2-contributor mixtures, but the lower degree of polymorphism per MH marker hindered the task of deconvolution with multiple contributors. MHs presented higher drop-in rates and lower drop-out rates, a higher capability to recover the minor contributor’s alleles and provided higher LR values than STRs, likely due to the much higher number of loci combined in the panel. Estimations of contributor ratios using EuroForMix showed promising results and marginal differences were found in these values between manually and automatically prepared libraries. Overall, results showed that the mixture detection performance of the MH panel was better or equal to the standard forensic autosomal STR panel, indicating microhaplotypes are informative markers for this purpose.

Burkholderia cenocepacia epigenetic regulator M.BceJIV simultaneously engages two DNA recognition sequences for methylation

Burkholderia cenocepacia is an opportunistic and infective bacterium containing an orphan DNA methyltransferase called M.BceJIV with roles in regulating gene expression and motility of the bacterium. M.BceJIV recognizes a GTWWAC motif (where W can be an adenine or a thymine) and methylates N6 of the adenine at the fifth base position. Here, we present crystal structures of M.BceJIV/DNA/sinefungin ternary complex and allied biochemical, computational, and thermodynamic analyses. Remarkably, the structures show not one, but two DNA substrates bound to the M.BceJIV dimer, with each monomer contributing to the recognition of two recognition sequences. We also show that methylation at the two recognition sequences occurs independently, and that the GTWWAC motifs are enriched in intergenic regions in the genomes of B. cenocepacia strains. We further computationally assess the interactions underlying the affinities of different ligands (SAM, SAH, and sinefungin) for M.BceJIV, as a step towards developing selective inhibitors for limiting B. cenocepacia infection.

Molecular species identification from seized dried genital organs: a case study of suspected Bengal monitor lizard (Varanus bengalensis)

The bifurcated hemipenes of any of the four species of Monitor lizards found in India is illegally traded under the name ‘Hatha Jodi’ (a plant root from Martynia annua). A rare plant root is misrepresented as a powerful charm capable of bringing property and good fortune to its possessor. As a result, there is a suspected large-scale poaching of monitors in India to fuel the trade of ‘Hatha Jodi’. With this regard, here we report a case where the Tamil Nadu Forest Department officers seized dried genital organs. We extracted DNA from the seized dried genital organs and amplified a partial fragment of the mitochondrial cytochrome-b gene (cytb). Then, generated DNA sequences were analyzed and confirmed that the dried genital organs were consistent with the Bengal monitor lizard with 99% similarity. In forensic case analysis, dried and processed samples are not preferred for DNA-based analysis. This is due to the low yield of DNA and increased PCR inhibitors, which lead to low success in such experiments. However, the present study demonstrated species identification through DNA analysis from seized dried genital organs and supported law enforcement in successfully prosecuting the case.

Why the post-identification era is long overdue: Commentary on the current controversy over forensic feature comparison as applied to forensic firearms examination

In this commentary, we critically review recurring arguments for and against the discipline of forensic feature comparison as applied to firearms examination from various commentators within and outside forensic science. One of the mainstream criticisms that we address, among others, is that the field cannot demonstrate sufficient proficiency and robustness based on empirical (i.e., black-box) studies. While the lack of empirically demonstrated examiner proficiency is a valid concern and a powerful concept in the short term (e.g., in admissibility proceedings), many critics reduce their discussion of forensic feature comparison solely to the need to measure and demonstrate proficiency through error rates. However, the exclusive focus on aggregate expert performance metrics, here referred to as examiner diagnosticism, remains a surface-level perspective. It provides an incomplete account of the field because these metrics do not represent—but are often confused with—the notion of the evidentiary value of findings, i.e., observations made on examined items in individual cases. We argue that examiner diagnosticism should be contrasted and complemented with the notion of feature selectivity, i.e., the diagnostic capacity of observed marks and features on examined items. We argue that forensic scientists should report and be probed on their ability to quantify feature selectivity (i.e., the probative value of findings). By ceasing to express source attribution opinions (identification/individualisation), which are now widely exposed as unscientific, the forensic feature comparison disciplines could move further into the long-awaited post-identification era pioneered by other fields such as forensic genetics.

CRISPR-Cas9 target-strand nicking provides phage resistance by inhibiting replication.

Cas endonucleases, like Cas9 and Cas12a, are RNA-guided immune effectors that provide bacterial defense against bacteriophages. Cas endonucleases rely on divalent metal ions for their enzymatic activities and to facilitate conformational changes that are required for specific recognition and cleavage of target DNA. While Cas endonucleases typically produce double-strand breaks (DSBs) in DNA targets, reduced, physiologically relevant Mg2+ concentrations and target mismatches can result in incomplete second-strand cleavage, resulting in the production of a nicked DNA. It remains poorly understood whether nicking by Cas endonucleases is sufficient to provide protection against phage. To address this, we tested phage protection by Cas9 nickases, in which only one of two nuclease domains is catalytically active. By testing a large panel of guide RNAs, we find that target strand nicking can be sufficient to provide immunity, while non-target nicking does not provide any additional protection beyond Cas9 binding. Target-strand nicking inhibits phage replication and can reduce the susceptibility of Cas9 to viral escape when targeting non-essential regions of the genome. Cleavage of the non-target strand by the RuvC domain is strongly impaired at low Mg2+ concentrations. As a result, fluctuations in the concentration of other biomolecules that can compete for binding of free Mg2+ strongly influences the ability of Cas9 to form a DSB at targeted sites. Overall, our results suggest that Cas9 may only nick DNA during CRISPR-mediated immunity, especially under conditions of low Mg2+ availability in cells.

Analysis of urine cell-free DNA in bladder cancer diagnosis by emerging bioactive technologies and materials.

Urinary cell-free DNA (UcfDNA) is gaining recognition as an important biomarker for diagnosing bladder cancer. UcfDNA contains tumor derived DNA sequences, making it a viable candidate for non-invasive early detection, diagnosis, and surveillance of bladder cancer. The quantification and qualification of UcfDNA have demonstrated high sensitivity and specificity in the molecular characterization of bladder cancer. However, precise analysis of UcfDNA for clinical bladder cancer diagnosis remains challenging. This review summarizes the history of UcfDNA discovery, its biological properties, and the quantitative and qualitative evaluations of UcfDNA for its clinical significance and utility in bladder cancer patients, emphasizing the critical role of UcfDNA in bladder cancer diagnosis. Emerging bioactive technologies and materials currently offer promising tools for multiple UcfDNA analysis, aiming to achieve more precise and efficient capture of UcfDNA, thereby significantly enhancing diagnostic accuracy. This review also highlights breakthroughs in detection technologies and substrates with the potential to revolutionize bladder cancer diagnosis in clinic.

The INSIGHT study: a randomized, Phase III study of ripretinib versus sunitinib for advanced gastrointestinal stromal tumor with KIT exon 11+17/18mutations.

Somatic KIT activating mutations drive most gastrointestinal stromal tumors (GISTs). Disease progression eventually develops with first-line imatinib, commonly due to KIT secondary mutations, and different kinase inhibitors have various levels of treatment efficacy dependent on specific acquired resistance mutations. Ripretinib is a broad-spectrum switch-control KIT/PDGFRA tyrosine kinase inhibitor for patients with advanced GIST who received prior treatment with threeor more kinase inhibitors, including imatinib. Exploratory baseline circulating tumor DNA analysis from the second-line INTRIGUE trial determined that patients with advanced GIST previously treated with imatinib harboring primary KIT exon 11mutations and secondary resistance mutations restricted to KIT exons 17/18 had greater clinical benefit with ripretinib versus sunitinib. We describe the rationale and design of INSIGHT (NCT05734105), an ongoing Phase III open-label study of ripretinib versus sunitinib in patients with advanced GIST previously treated with imatinib exclusively harboring KIT exon 11+17/18mutations detected by circulating tumor DNA.Clinical Trial Registration: NCT05734105 (ClinicalTrials.gov).

Toward Analysis at the Point of Need: A Digital Microfluidic Approach to Processing Multi-Source Sexual Assault Samples.

Forensic case samples collected in sexual assaults typically contain DNA from multiple sources, which complicates short-tandem repeat (STR) profiling. These samples are typically sent to a laboratory to separate the DNA from sperm and non-sperm sources prior to analysis. Here, the automation and miniaturization of these steps using digital microfluidics (DMF) is reported, which may eventually enable processing sexual assault samples outside of the laboratory, at the point of need. When applied to vaginal swab samples collected up to 12h post-coitus (PC), the new method identifies single-source (male) STR profiles. When applied to samples collected 24-72h PC, the method identifies mixed STR profiles, suggesting room for improvement and/or potential for data deconvolution. In sum, an automated, miniaturized sample pre-processing method for separating the DNA contained in sexual assault samples is demonstrated. This type of automated processing using DMF, especially when combined with Rapid DNA Analysis, has the potential to be used for processing of sexual assault samples in hospitals, police offices, and other locations outside of the laboratory.

Structural basis of DNA recognition by BEN domain proteins reveals a role for oligomerization in unmethylated DNA selection by BANP.

The BEN domain is a newly discovered type of DNA-binding domain that exists in a variety of species. There are nine BEN domain-containing proteins in humans, and most have been shown to have chromatin-related functions. NACC1 preferentially binds to CATG motif-containing sequences and functions primarily as a transcriptional coregulator. BANP and BEND3 preferentially bind DNA bearing unmethylated CpG motifs, and they function as CpG island-binding proteins. To date, the DNA recognition mechanism of quite a few of these proteins remains to be determined. In this study, we solved the crystal structures of the BEN domains of NACC1 and BANP in complex with their cognate DNA substrates. We revealed the details of DNA binding by these BEN domain proteins and unexpectedly revealed that oligomerization is required for BANP to select unmethylated CGCG motif-containing DNA substrates. Our study clarifies the controversies surrounding DNA recognition by BANP and demonstrates a new mechanism by which BANP selects unmethylated CpG motifs and functions as a CpG island-binding protein. This understanding will facilitate further exploration of the physiological functions of the BEN domain proteins in the future.

The dimensions of ‘forensic biosecurity’ in genetic and facial contexts

AbstractThis article seeks to examine the co-productions of security and emerging technologies in the two contexts of forensic genetics and forensic facial identification. These surfacing co-productions, deemed here as ‘forensic biosecurity’, are evolving rapidly in both theoretical and practical terms. Definitions and conceptualisations of security are contingent and multiple, impacting forensic biological techniques and innovations in both predictable and unpredictable ways. The military, counter-terrorism, law enforcement, immigration, customs, border patrol, mass disasters, cold case reviews, health, defence, private security, and biometric applications are just a few of the many security environments where forensic biological techniques are applied. The continual development of variations in forensic genetics and facial identification renders a futher blurring of traditional evidence with that of intelligence. Drawing in particular from Joly’s (in: S. Hilgartner, C. Miller, and R. Hagendijk (eds) Science and democracy: Making knowledge and making power in the biosciences and beyond, Taylor and Francis, London, 2015) work on emerging technologies, forensic biosecurity is analysed from a science and technology studies (STS) perspective. An emerging technology in the initial stages is thought to be highly flexible with the potential impacts on society and criminal justice being possibly difficult to predict. Once the science and/or technology has become entrenched and mainstream, it may be difficult to change. The enthusiasm portrayed by law enforcement and security agencies regarding emerging technologies, shows that it is important to remain somewhat cautious about the proliferation of these techniques. While such science and technologies appear to be effective and innovative in the present, it is difficult to accurately forecast or predict the future consequences of such innovations.