Next-generation Sequencing Techniques Research Articles

Long-Read Nanopore-Based Sequencing of Anelloviruses

Routinely used metagenomic next-generation sequencing (mNGS) techniques often fail to detect low-level viremia (<104 copies/mL) and appear biased towards viruses with linear genomes. These limitations hinder the capacity to comprehensively characterize viral infections, such as those attributed to the Anelloviridae family. These near ubiquitous non-pathogenic components of the human virome have circular single-stranded DNA genomes that vary in size from 2.0 to 3.9 kb and exhibit high genetic diversity. Hence, species identification using short reads can be challenging. Here, we introduce a rolling circle amplification (RCA)-based metagenomic sequencing protocol tailored for circular single-stranded DNA genomes, utilizing the long-read Oxford Nanopore platform. The approach was assessed by sequencing anelloviruses in plasma drawn from people who inject drugs (PWID) in two geographically distinct cohorts. We detail the methodological adjustments implemented to overcome difficulties inherent in sequencing circular genomes and describe a computational pipeline focused on anellovirus detection. We assessed our protocol across various sample dilutions and successfully differentiated anellovirus sequences in conditions simulating mixed infections. This method provides a robust framework for the comprehensive characterization of circular viruses within the human virome using the Oxford Nanopore.

First parechovirus reported case in Saudi Arabia in hospitalized immunocompromised adult patient

Human parechovirus, a member of the Picornaviridae family (PeVs), can lead to severe infections, including severe meningitis, meningoencephalitis, and sepsis-like syndrome. We report a case of human parechovirus-related encephalitis in a 52-year-old woman diagnosed with glioblastoma multiforme. She underwent surgical resection in June 2022. Unfortunately, her disease recurred, and she underwent a second resection in August 2022, followed by radiation therapy and Temozolomide therapy. She presented to the hospital with acute confusion followed by seizures, necessitating intubation for airway support. A cerebrospinal fluid (CSF) sample was obtained and processed using the Biofire FilmArray, which reported the detection of HSV-1. Despite being on Acyclovir, the patient did not show signs of improvement. Consequently, a second CSF sample was obtained and sent for next-generation sequencing (NGS), which returned a positive result for Parechovirus. In this presented case, the patient exhibited symptoms of an unknown infectious cause. The utilization of NGS and metagenomic analysis helped identify Parechovirus as the primary pathogen present, in addition to previously identified HSV. This comprehensive approach facilitated a thorough assessment of the underlying infection and guided targeted treatment. In conclusion, the application of NGS techniques and metagenomic analysis proved instrumental in identifying the root cause of the infection.

A high-dose of ursodeoxycholic acid treatment alleviates liver inflammation by remodeling gut microbiota and bile acid profile in a mouse model of non-alcoholic steatohepatitis.

Ursodeoxycholic acid (UDCA) is a hydrophilic bile acid commonly used for treating cholestatic liver disease. However, its efficacy on non-alcoholic steatohepatitis (NASH) was controversial. This study aimed to investigate the impact of a high dosage of UDCA on a mouse model of NASH. Forty 6-week-old mice were fed a high-fat high-cholesterol (HFHC) diet for 12 weeks to establish a mouse model of NASH, and then divided into four groups: two groups transitioned to a normal diet, and the other two groups maintained the HFHC diet. Each group was administered a daily dosage of 300 mg/kg of UDCA or saline for a period of 8 weeks. The 16 s ribosomal RNA genes extracted from mice fecal pellets were sequenced using next-generation sequencing techniques. Serum bile acid profiles were quantified using liquid chromatography electrospray ionization tandem mass spectrometry method. The results showed that UDCA treatment ameliorated liver inflammation, without affecting liver fibrosis. UDCA treatment reduced the relative abundance of the genera Bacteroides, Parabacteroides, and Intestinimonas, whereas increased the relative abundance of the genera norank_f_Muribaculaceae and Parasutterella in the HFHC-maintaining groups. The serum levels of total bile acids and total primary bile acids increased, whereas those of endogenous primary bile acids decreased after UDCA treatment. Correlation analysis showed that primary bile acids were negatively correlated with the genera norank_f_Christensenellaceae and unclassified_f_Ruminococcaceae. In conclusion, a high dosage of UDCA can alleviate liver inflammation, probably by modifying the composition of gut microbiota and serum bile acid profiles in NASH mice.

Differences of ocular oscillations and neuro-retinal structures in patients with nystagmus caused by GPR143 and FRMD7 gene variants.

Mutations of G protein-coupled receptor 143 (GPR143) and FERM domain containing 7 (FRMD7) may result in congenital nystagmus (CN) in the first 6 months of life. We aimed to compare the differences in ocular oscillations between patients with these two gene mutations as well as the functional and structural changes in their retinas and visual pathways. Medical records were retrospectively reviewed to identify patients of congenital nystagmus with confirmed mutations in either GPR143 or FMRD7 genes from January 2018 to May 2023. The parameters of the ocular oscillations were recorded using Eyelink 1000 Plus. The retinal structure and function were evaluated using optical coherence tomography and multi-focal electroretinography (mERG). The visual pathway and optical nerve projection were evaluated using visual evoked potentials. The next-generation sequencing technique was used to identify the pathogenic variations in the disease-causing genes for CN. Twenty nystagmus patients of GPR143 and 21 patients of FMRD7 who had been confirmed by molecular testing between January 2018 and May 2023 were included. Foveal hypoplasia was detected only in patients with the GPR143 pathogenic variant. mERG examination showed a flat response topography in the GPR143 group compared to the FRMD7 group. VEP showed that bilateral amplitude inconsistency was detected only in the patients with GPR143 gene mutation. The amplitude and frequency of the ocular oscillations were not found to differ between patients with two different genetic mutations. Although the etiology and molecular mechanisms are completely different between CN patients, they may have similar ocular oscillations. A careful clinical examination and electrophysiological test will be helpful in making a differential diagnosis. Our novel identified variants will further expand the spectrum of the GPR143 and FRMD7 variants.

Isolation, Identification, and Pathogenicity of a Goose Astrovirus Genotype 1 Strain in Goslings in China.

Goose astrovirus genotype 1 (GAstV-1) has emerged in goose farms in some provinces of China in recent years and is considered to be one of the pathogens of gout in goslings in China. However, few studies have been conducted on the dynamic distribution, tissue tropism, and pathogenesis of GAstV-1 in goslings. In 2022, an epidemiological investigation of goose astrovirus (GAstV) in goslings was conducted in seven provinces of China. During the investigation, a GAstV-1 designated as GAstV-JSXZ was identified in the kidney of an 8-day-old gosling and was successfully isolated from a goose embryo. The full genome sequence of GAstV-JSXZ was determined using the next-generation sequencing technique. The complete genome of GAstV-JSXZ was 7299-nt-long. Interestingly, the phylogenetic analysis revealed that Chinese GAstV-1 has formed two distinct subgroups based on the ORF 2 genomes, designated GAstV-1 1a and GAstV-1 1b. The GAstV-JSXZ shared the highest identity with GAstV-1 1a strain FLX and TZ03 in nucleotides (ORF1a: 98.3-98.4%; ORF1b: 92.3-99.1%; ORF2: 95.8-98.8%) and amino acid sequences (ORF1a: 99.4-99.5%; ORF1b: 98.2-98.8%; ORF2: 97.0-99.4%). To evaluate the pathogenicity of GAstV-1, 1-day-old goslings were inoculated with the virus by oral and subcutaneous injection routes, respectively. The results revealed that the virus causes extensive pathological organ damage, especially in the kidney, liver, and thymus. Virus-specific genomic RNA could be detected in the cloacal swabs and tissues of infected goslings throughout the experiment. The viral copy numbers examined in the kidney and intestine were the highest, followed by the liver and spleen. These results are likely to provide a new understanding of the pathogenicity of GAstV-1 in geese.

Genetic determinants of global developmental delay and intellectual disability in Ukrainian children

BackgroundGlobal developmental delay or intellectual disability usually accompanies various genetic disorders as a part of the syndrome, which may include seizures, autism spectrum disorder and multiple congenital abnormalities. Next-generation sequencing (NGS) techniques have improved the identification of pathogenic variants and genes related to developmental delay. This study aimed to evaluate the yield of whole exome sequencing (WES) and neurodevelopmental disorder gene panel sequencing in a pediatric cohort from Ukraine. Additionally, the study computationally predicted the effect of variants of uncertain significance (VUS) based on recently published genetic data from the country’s healthy population.MethodsThe study retrospectively analyzed WES or gene panel sequencing findings of 417 children with global developmental delay, intellectual disability, and/or other symptoms. Variants of uncertain significance were annotated using CADD-Phred and SIFT prediction scores, and their frequency in the healthy population of Ukraine was estimated.ResultsA definitive molecular diagnosis was established in 66 (15.8%) of the individuals. WES diagnosed 22 out of 37 cases (59.4%), while the neurodevelopmental gene panel identified 44 definitive diagnoses among the 380 tested patients (12.1%). Non-diagnostic findings (VUS and carrier) were reported in 350 (83.2%) individuals. The most frequently diagnosed conditions were developmental and epileptic encephalopathies associated with severe epilepsy and GDD/ID (associated genes ARX, CDKL5, STXBP1, KCNQ2, SCN2A, KCNT1, KCNA2). Additionally, we annotated 221 VUS classified as potentially damaging, AD or X-linked, potentially increasing the diagnostic yield by 30%, but 18 of these variants were present in the healthy population of Ukraine.ConclusionsThis is the first comprehensive study on genetic causes of GDD/ID conducted in Ukraine. This study provides the first comprehensive investigation of the genetic causes of GDD/ID in Ukraine. It presents a substantial dataset of diagnosed genetic conditions associated with GDD/ID. The results support the utilization of NGS gene panels and WES as first-line diagnostic tools for GDD/ID cases, particularly in resource-limited settings. A comprehensive approach to resolving VUS, including computational effect prediction, population frequency analysis, and phenotype assessment, can aid in further reclassification of deleterious VUS and guide further testing in families.

NGS Technique for Palindromic Sequencing of DNA Through Effective PST-PCR

DNA Sequencing technologies have been in use since 1970 and has diversified to much more effective transformations till the date. Initially due to certain drawbacks like cost, time period and requirement of toxic and radioactive elements for the compilation of the process, it remained unintroduced to research setting for complex data in earlier times. One of a technique named as the Sanger technique had more practical approach for sequencing the desired data of the fragments. But the need of DNA sequencing surged after the commencement of the Human Genome Project (HGP) which was a 13 year long collaboration to sequence human genome for understanding its applicable uses.1 At the current stage, the progress moved towards Next Generation Sequencing (NGS) to   sequence the fragments of DNA for a better acknowledgement but somehow this did not reported for a fair outcome for palindromic DNA while sequencing. In this rugged sequencing platforms, Roche’s 454 with emulsion PCR technique amplified the templates through beads which later went through pyrosequencing with DNA Polymerase gave the desired output but had a major drawback of high cost.2 Therefore, this study deals with effective PST – PCR technique for studying palindromic DNA in NGS and how it can be considered to fit in all advantages for the above task.

Abstract 5133: Gastric cancer carrying FAT4 mutations associated with favorable prognosis in comparison to wild-type: Results from Real-World Cohorts

Abstract Introduction: Gastric cancer (GC) is a complex and heterogeneous disease with variable clinical outcomes. Identifying prognostic factors that can reliably predict patient outcomes is crucial for personalized treatment strategies. In this study, we aimed to investigate the impact of mutations in the FAT4 gene as potential prognostic factors in gastric cancer. Methods: We conducted a comprehensive analysis of genomic data from a cohort of 236 gastric cancer patients to identify mutations in the FAT4 gene and validated it using the TCGA cohort. The mutational landscape of FAT4 was analyzed using next-generation sequencing (NGS) techniques. Clinical data, including patient demographics, tumor characteristics, and survival outcomes, were collected and correlated with the presence of FAT4 cadherin mutations. Results: In the real-world cohort, the occurrence of mutations of FAT4 was 19.1% (45/236), while in the TCGA cohort, it was 21.0% (89/423). Specifically, the mutation rates in the single cadherin functional domain of FAT4 were 10.2% (24/236) in the real-world cohort and 8.0% (34/423) in the TCGA cohort. The mutation rates for multiple cadherin sites were 2.5% (6/236) and 2.1% (9/423) in the real-world and TCGA cohorts, respectively. Survival analysis revealed that patients with FAT4 mutations had a significantly better prognosis compared to those with wild-type FAT4 (p=0.0357). Patients with multiple cadherin mutations had a better prognosis compared to those with single cadherin mutations in real-world cohorts (p=0.0651). No significant difference was observed in the TCGA cohort between single and multiple cadherin mutations (p = 0.2003), although FAT4 mutations exhibited a significant improvement in prognosis compared to wild-type patients in the TCGA cohort (p = 0.0226). Conclusion: Our findings indicate that FAT4 mutations confer a favorable prognosis in gastric cancer patients. The presence of FAT4 mutations was associated with improved survival compared to patients with wild-type FAT4. These findings underscore the potential value of FAT4 mutation status as a prognostic factor, guiding personalized treatment approaches for individuals with gastric cancer. Citation Format: Shu Wang, Haoyuan Wang, Yuxuan Ma, Yuhao Wang, Yan Zhao, Chaosheng Peng, Weiming Duan, Feilong Zhao, Jianjun Yang. Gastric cancer carrying FAT4 mutations associated with favorable prognosis in comparison to wild-type: Results from Real-World Cohorts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5133.

Novel pathogenic variants of SLC38A8 gene and literature review.

This study aimed to analyze the clinical and genetic characteristics of 6 Chinese patients with foveal hypoplasia (FH) caused by the variants of solute carrier family 38 member 8 (SLC38A8), and to describe the genotype and phenotype of SLC38A8 variants from previous literature. All subjects underwent comprehensive ophthalmic examinations. Optical coherence tomography (OCT) was performed to evaluate the structural grade of FH. Pathogenic variants of SLC38A8 gene were identified using panel-based next-generation sequencing and direct Sanger sequencing techniques. Further, all previously reported cases of SLC38A8 variants were re-analyzed together with the novel ones identified in this study. Nystagmus and FH were present in 6 patients with variants of SLC38A8 gene, accompanied by a normal anterior segment. Grade 4 FH was identified in 4 patients. A total of 12 variants of SLC38A8 gene were identified, including 9 novel variants. Systematical analysis revealed that half of the variants (30/60) were missense, the majority of which (23/30) were distributed in the transmembrane (TM) domains. Grade 4 FH was detected in the majority of patients (66%, 23/35). There was no statistical difference in the clinical features between the subgroups of patients with 0, 1 and 2 missense variants. Severe arrest of foveal development was identified in patients with variants of SLC38A8. This study provides a brief summary of the clinical and genetic characteristics of the pathogenic SLC38A8 variants, which is helpful in the differentiation diagnosis of FH.

Abstract 6285: Defining androgen receptor function and the effects of PARP inhibition in BRCA1/2-deficient vs. proficient prostate cancer

Abstract Mutation or loss of the tumor suppressor genes BRCA1 and BRCA2 promotes the development of aggressive prostate cancer with poor outcomes and a high risk of metastatic relapse. Approximately 15% of metastatic prostate tumors are BRCA1/2-deficient. These tumors are frequently resistant to standard-of-care treatments that block androgen receptor (AR) function, although the mechanisms underlying this effect remain unclear. PARP inhibitors are synthetically lethal with BRCA1/2-deficiency and are commonly used as a late-line treatment in metastatic prostate cancer; however, both preclinical and clinical data have provided conflicting results on whether PARP inhibitors can be effective in BRCA1/2-proficient prostate tumors. BRCA1, BRCA2, PARP-1, and PARP-2 all have proposed roles in regulating transcription and the chromatin landscape. We therefore hypothesized that loss of BRCA1, BRCA2, and/or inhibition of PARP modulates AR function through changes in global chromatin structure and transcriptional pathways. We used patient-derived xenograft models and next-generation sequencing techniques to profile AR function in BRCA1/2-deficient vs. proficient prostate tumors. We found that loss of BRCA1 and BRCA2 is associated with chromatin accessibility changes, and differentially accessible regions correlate with DNA binding motifs for AR and AR cofactors. ChIP-seq for AR in these tumors demonstrated that BRCA1/2-deficiency is associated with an altered AR cistrome and a global decrease in AR genomic binding. Corresponding RNA-seq data confirmed a downregulated androgen response in BRCA1/2-deficient tumors. In cell line models, inhibition of PARP1 and PARP1/2 inhibited AR-driven transcription. Combining PARP inhibition with either androgen deprivation or the AR antagonist enzalutamide dampened the growth-inhibitory effects of PARP inhibitor treatment. Together, these results indicate that BRCA1/2-deficiency and PARP inhibition modulate AR function in prostate cancer. Citation Format: Nicole A. Traphagen, Esme Wheeler, Rong Li, Xintao Qiu, Myles Brown. Defining androgen receptor function and the effects of PARP inhibition in BRCA1/2-deficient vs. proficient prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6285.

First Record of Comparative Plastid Genome Analysis and Phylogenetic Relationships among Corylopsis Siebold & Zucc. (Hamamelidaceae).

Corylopsis Siebold & Zucc. (Hamamelidaceae) is widely used as a horticultural plant and comprises approximately 25 species in East Asia. Molecular research is essential to distinguish Corylopsis species, which are morphologically similar. Molecular research has been conducted using a small number of genes but not in Corylopsis. Plastid genomes of Corylopsis species (Corylopsis gotoana, Corylopsis pauciflora, and Corylopsis sinensis) were sequenced using next-generation sequencing techniques. Repeats and nucleotide diversity that could be used as DNA markers were also investigated. A phylogenetic investigation was carried out using 79 protein-coding genes to infer the evolutionary relationships within the genus Corylopsis. By including new plastomes, the overall plastid genome structure of Corylopsis was similar. Simple sequence repeats of 73-106 SSRs were identified in the protein-coding genes of the plastid genomes, and 33-40 long repeat sequences were identified in the plastomes. The Pi value of the rpl33_rps18 region, an intergenic spacer, was the highest. Phylogenetic analysis demonstrated that Corylopsis is a monophyletic group and Loropetalum is closely related to Corylopsis. C. pauciflora, C. gotoana, and C. spicata formed a clade distributed in Japan, whereas C. sinensis, C. glandulifera, and C. velutina formed a clade that was distributed in China.

A Second Fungal Outbreak in Castañar Cave, Spain, Discloses the Fragility of Subsurface Ecosystems

Castañar is a cave with strict visitor control measures since it was open to public visits in 2003. However, in recent years, the cave suffered two fungal outbreaks, the first in 2008 and controlled by cleaning the contaminated sediments and subsequent closure of the cave until 2014. The cave was reopened but limited to a maximum of 450 visitors/year. Despite these restrictions on visit, the cave experienced a second outbreak in 2021, originating from the installation of a steel grating walkway, aiming at protecting the ground sediments from the visitors’ footsteps. Here, we conducted an analysis using Next-Generation Sequencing and culture-dependent techniques to investigate the fungal communities related to the second outbreak and compare with those present before the cave suffered the outbreak. The results show that the most abundant fungi involved in the 2021 outbreak were already detected in 2020, and even in 2008 and 2009, although the main species that originating both outbreaks were different, likely due to the different carbon sources introduced into the cave.

STING is significantly increased in high-grade glioma with high risk of recurrence

ABSTRACT In this study, we aimed to comprehensively characterize the potential relationships among the frequently mutated genes, well-known homologous recombination repair (HRR) proteins, and immune proteins in glioma from a clinical perspective. A total of 126 surgical tissues from patients initially diagnosed with glioma were included. The genetic alterations were tested using the targeted next-generation sequencing technique. The expression of HRR proteins, immune proteins, and genetic alteration-related proteins were detected using immunostaining. Integrated analysis showed that ATRX is positively correlated with STING in high-grade glioma (HGG) with wild-type ATRX and IDH1. Then, a relapse predictive risk-scoring model was established using the least absolute shrinkage and selection operator regression algorithms. The scores based on the expression of ATRX and STING significantly predict the recurrence for glioma patients, which further predict the survival for specific subgroups, characterized with high expression of RAD51 and wild-type TERT. Moreover, STING is significantly higher in patients with high relapse risk. Interestingly, STING inhibitors and agonists both suppress the growth of HGG cells, regardless of their STING levels and STING pathway activity, whereas RAD51 inhibitor B02 is found to exclusively sensitize HGG cells with high expression of STING to temozolomide in vitro and in vivo. Overall, findings in the study not only reveal that ATRX is closely correlated with STING to drive the relapse of HGG, but also provide a STING-guided combined strategy to treat patients with aggressive gliomas. Translation of these findings will ultimately improve the outcomes for ATRX and IDH1 genomically stratified subgroups in HGG.

Nationwide data from comprehensive genomic profiling assays for detecting driver oncogenes in non-small cell lung cancer.

Driver oncogenes are investigated upfront at diagnosis using multi-CDx systems with next-generation sequencing techniques or multiplex reverse-transcriptase polymerase chain reaction assays. Additionally, from 2019, comprehensive genomic profiling (CGP) assays have been available in Japan for patients with advanced solid tumors who had completed or were expected to complete standard chemotherapy. These assays are expected to comprehensively detect the driver oncogenes, especially for patients with non-small cell lung cancer (NSCLC). However, there are no reports of nationwide research on the detection of driver oncogenes in patients with advanced NSCLC who undergo CGP assays, especially in those with undetected driver oncogenes at diagnosis. In this study, we investigated the proportion of driver oncogenes detected in patients with advanced NSCLC with undetectable driver oncogenes at initial diagnosis and in all patients with advanced NSCLC who underwent CGP assays. We retrospectively analyzed data from 986 patients with advanced NSCLC who underwent CGP assays between August 2019 and March 2022, using the Center for Cancer Genomics and Advanced Therapeutics database. The proportion of driver oncogenes newly detected in patients with NSCLC who tested negative for driver oncogenes at diagnosis and in all patients with NSCLC were investigated. Driver oncogenes were detected in 451 patients (45.7%). EGFR was the most common (16.5%), followed by KRAS (14.5%). Among the 330 patients with undetected EGFR, ALK, ROS1, and BRAF V600E mutations at diagnosis, 81 patients (24.5%) had newly identified driver oncogenes. CGP assays could be useful to identify driver oncogenes in patients with advanced NSCLC, including those initially undetected, facilitating personalized treatment.

Bioinformatic Sweeties: a unified portal for characterizing human proteins and their variants

Next-generation sequencing techniques provide an unprecedented characterisation of human Variants of Unknown Significance (VUS). Single-residue variations are collected in public databases and associated to diseases and phenotypes. However, for detailing at molecular level mechanisms involved in the onset of diseases, variants need structural and functional annotation. Here we propose a new portal called Bioinformatic Sweeties, collecting resources ranging from databases for human protein annotation to computational methods for predicting impact of variants. The tools, included in the portal, allow computing different protein properties, ranging from solvent accessible surface to stability and interactions and do not require login or installation. The portal, speeding up the variant characterisation process, is available at: https://bioinformaticsweeties.biocomp.unibo.it

APPLICATION OF THE NEXT GENERATION SEQUENCING IN BIOLOGY AND MEDICINE

Next-Generation Sequencing (NGS), also known as high-throughput sequencing, refers to a set of modern DNA sequencing technologies that have revolutionized the field of genomics. Advantages of NGS techniques involving high speed (parallel sequencing is faster than traditional methods, allowing researchers to obtain results more quickly), cost-effectiveness (ability to sequence multiple fragments simultaneously reduces the cost per base compared to traditional sequencing), and scalability (platforms can be scaled to accommodate varying levels of throughput depending on experimental needs). NGS has significantly accelerated genomics research, enabling breakthroughs in fields such as personalized medicine, cancer genomics, and evolutionary biology. However, challenges such as data analysis complexity, error rates, and cost still exist and are areas of ongoing research and improvement within the field of sequencing technologies. Paper contains the brief explanation of the current NGS platforms and their features. NGS biomedical application is described with the main advantages and abilities of the analysed tools.

Sequence analysis and secondary structure prediction of autosomal STR alleles using next generation sequencing (NGS) data

The inception of NGS technology in forensic DNA analysis explores the sequence-based alleles in STR markers. This allows the in-depth analysis of observed STR allelic sequences to understand their nature, stability, inheritance, and possible generation of artifacts during their analysis. In the current study, 100 allelic sequences at 20 STR markers generated using the NGS technique were analyzed for their sequence topographies and prediction of secondary structures. The G + C content of the alleles observed in 20 STR markers used in this study varied from 58.65 ± 1.367% (D2S1338) to 7.62 ± 0.844% (D12ATA63). The average exact mass of one stand and for the opposite stand mass was found to be highest in FGA (25,963.248 ± 1623.271; 27,501.720 ± 1712.691), whereas, D4S2408 generated the lowest exact mass of one stand and for the opposite stand mass (11,136.354 ± 1521.757; 11,582.021 ± 1585.486). As expected, none of the STR markers showed the presence of open reading frames, Codons, and CRISPR sequences. Three STR markers viz. D2S1338, TH01, and D5S2800 showed the presence of restriction sites for Cac8I, TspGWI, TspDTI, AccI, and Hpy8I enzymes. Phylogenetic analysis reveals the close association of alleles between the D12ATA63 and D19S433 markers. Stable pseudoknots were predicted at alleles of D2S1338 showing an average energy of −0.76 with the highest number of nucleotides present in the pseudoknots i.e., 21.33, suggesting this marker is more prone to generate amplification artifacts.

Genetic interrogation for sequence and copy number variants in systemic lupus erythematosus.

Early-onset systemic lupus erythematosus presents with a more severe disease and is associated with a greater genetic burden, especially in patients from Black, Asian or Hispanic ancestries. Next-generation sequencing techniques, notably whole exome sequencing, have been extensively used in genomic interrogation studies to identify causal disease variants that are increasingly implicated in the development of autoimmunity. This Review discusses the known casual variants of polygenic and monogenic systemic lupus erythematosus and its implications under certain genetic disparities while suggesting an age-based sequencing strategy to aid in clinical diagnostics and patient management for improved patient care.

Complete mitochondrial genome of Basilepta melanopus Lefèvre, 1893 (coleoptera: chrysomelidae: eumolpinae), a tea pest from Southern China

The tea pest, Basilepta melanopus Lefèvre 1893 (Chrysomelidae), belongs to the subfamily Eumolpinae. In this study, the complete mitochondrial genome sequence of B. melanopus from southern China was sequenced using the next-generation sequencing technique, assembled, and annotated using bioinformatics tools. The complete mitochondrial genome was 15,905 bp in length. The overall GC content was 22.51%, in which the percentages for the bases A, T, C, and G were 41.23%, 36.26%, 8.92%, and 13.59%, respectively. Thirty-seven genes were predicted, including 13 protein-coding, 22 transfer RNA, and two ribosomal RNA genes. Phylogenetic analysis based on the complete mitochondrial genome sequences of 18 Chrysomelidae taxa revealed that B. melanopus was closely related to Basilepta fulvipes.

The HIV-1 reservoir landscape in persistent elite controllers and transient elite controllers.

Persistent controllers (PC) maintain antiretroviral-free HIV-1 control indefinitely over time while transient controllers (TC) eventually lose virological control. It is essential to characterize the quality of the HIV reservoir of these phenotypes to identify the factors that lead to HIV progression and to open new avenues in HIV cure strategies. The characterization of HIV-1 reservoir, from peripheral blood mononuclear cells, was performed using next-generation sequencing techniques, such as full-length individual and matched integration site proviral sequencing (FLIP-seq; MIP-seq). PC and TC before losing virological control, presented significantly lower total, intact and defective proviruses compared to participants on antiretroviral therapy (ART). No differences were found in total and defective proviruses between PC and TC. However, intact provirus levels were lower in PC compared to TC, being the intact/defective HIV-DNA ratio significantly higher in TC. Clonally expanded intact proviruses were found only in PC and located in centromeric satellite DNA or zinc-finger genes, both associated with heterochromatin features. In contrast, sampled intact proviruses were located in permissive genic euchromatic positions in TC. These results suggest the need for, and can give guidance to the design of, future research to identify a distinct proviral landscape that may be associated with the persistent control of HIV-1 without ART. Instituto de Salud Carlos III (FI17/00186, FI19/00083, MV20/00057 PI18/01532, PI19/01127 and PI22/01796), Consejería de Economía, Conocimiento, Empresas y Universidad, Junta de Andalucía (PI20/1276), Gilead Fellowships (GLD22/00147) and I+D+iFEDER Andalucía 2014-2020 (US-1380938).