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This study evaluates long-read and short-read sequencing for mitochondrial DNA (mtDNA) heteroplasmy detection. 592,315 bootstrapped datasets generated from two single-nucleotide mismatched ultra-deep sequenced mtDNA samples were used to assess basecalling error and accuracy, limit of heteroplasmy detection, and heteroplasmy detection across various coverage depths. Results showed high Phred scores of data with GC-rich sequence bias for long reads. Limit of detection of 12% heteroplasmy was identified, showing strong correlation (R 2  ≥ 0.955) with expected heteroplasmy but underreporting tendency of high-level variants. Nanopore sequencing shows potential for direct applicability in mitochondrial diseases diagnostics, but stringent validation processes to ensure diagnostic result quality are required., (© 2024. The Author(s).)

Introduction: Hypertriglyceridemia (HTG) is a complex disorder caused by genetic and environmental factors that frequently results from loss-of-function variants in the gene encoding lipoprotein lipase (LPL). Heterozygous patients have a range of symptoms, while homozygous LPL deficiency presents with severe symptoms including acute pancreatitis, xanthomas, and lipemia retinalis., Methods: We described the clinical characteristics of three Slovenian patients (an 8-year-old female, an 18-year-old man, and a 57-year-old female) and one Pakistani patient (a 59-year-old male) with LPL deficiency. We performed next-generation sequencing (NGS) targeting all coding exons and intron-exon boundaries of the LPL gene, and Sanger sequencing for variant confirmation. In addition, we performed a systematic literature review of all cases with three identified variants and described their clinical characteristics., Results: Two Slovenian patients with a heterozygous pathogenic variant NM_000237.3:c.984G>T (p.Met328Ile) were diagnosed within the first three years of life and had triglyceride (TG) values of 16 and 20 mmol/L. An asymptomatic Pakistani patient with TG values of 36.8 mmol/L until the age of 44 years, was identified as heterozygous for a pathogenic variant NM_000237.3:c.724G>A (p.Asp242Asn). His TG levels dropped to 12.7 mmol/L on dietary modifications and by using fibrates. A Slovenian patient who first suffered from pancreatitis at the age of 18 years with a TG value of 34 mmol/L was found to be homozygous for NM_000237.3:c.337T>C (p.Trp113Arg)., Conclusions: Patients with LPL deficiency had high TG levels at diagnosis. Homozygous patients had worse outcomes. Good diet and medication compliance can reduce severity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Ain, Cevc, Marusic, Sikonja, Sadiq, Sustar, Mlinaric, Kovac, Batool, Khan, Trebusak Podkrajsek, Bizjan, Battelino, Fras, Ajmal and Groselj.)

Aim: To evaluate the accuracy of two PCR-based techniques for detecting SARS-CoV-2 variant Alpha (B.1.1.7). Materials & methods: A multicenter prospective cohort with 1137 positive specimens from Slovenia was studied. A mutation-based assay (rTEST-COVID-19 qPCR B.1.1.7 assay) and amplification curve pattern analysis of the Allplex SARS-CoV-2 assay were compared with whole-genome sequencing. Results: SARS-CoV-2 variant Alpha was detected in 155 samples (13.6%). Sensitivity and specificity were 98.1 and 98.0%, respectively, for the rTEST-COVID-19 qPCR B.1.1.7 assay and 97.4 and 97.5%, respectively, for amplification curve pattern analysis. Conclusion: The good analytical performance of both methods was confirmed for the preliminary identification of SARS-CoV-2 variant Alpha. This cost-effective principle for screening SARS-CoV-2 populations is also applicable to other emerging variants and may help to conserve some whole-genome sequencing resources.

Background: Due to nonspecific symptoms, rare dyslipidaemias are frequently misdiagnosed, overlooked, and undertreated, leading to increased risk for severe cardiovascular disease, pancreatitis and/or multiple organ failures before diagnosis. Better guidelines for the recognition and early diagnosis of rare dyslipidaemias are urgently required. Methods: Genomic DNA was isolated from blood samples of a Pakistani paediatric patient with hypertriglyceridemia, and from his parents and siblings. Next-generation sequencing (NGS) was performed, and an expanded dyslipidaemia panel was employed for genetic analysis. Results: The NGS revealed the presence of a homozygous missense pathogenic variant c.230G>A (NM_178172.6) in exon 3 of the GPIHBP1 (glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1) gene resulting in amino acid change p.Cys77Tyr (NP_835466.2). The patient was 5.5 years old at the time of genetic diagnosis. The maximal total cholesterol and triglyceride levels were measured at the age of 10 months (850.7 mg/dl, 22.0 mmol/L and 5,137 mg/dl, 58.0 mmol/L, respectively). The patient had cholesterol deposits at the hard palate, eruptive xanthomas, lethargy, poor appetite, and mild splenomegaly. Both parents and sister were heterozygous for the familial variant in the GPIHBP1 gene. Moreover, in the systematic review, we present 62 patients with pathogenic variants in the GPIHBP1 gene and clinical findings, associated with hyperlipoproteinemia. Conclusion: In a child with severe hypertriglyceridemia, we identified a pathogenic variant in the GPIHBP1 gene causing hyperlipoproteinemia (type 1D). In cases of severe elevations of plasma cholesterol and/or triglycerides genetic testing for rare dyslipidaemias should be performed as soon as possible for optimal therapy and patient management., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sustar, Groselj, Khan, Shafi, Khan, Kovac, Bizjan, Battelino and Sadiq.)

Monogenic obesity is a severe, genetically determined disorder that affects up to 1/1000 newborns. Recent reports on potential new therapeutics and innovative clinical approaches have highlighted the need for early identification of individuals with rare genetic variants that can alter the functioning of the leptin-melanocortin signalling pathway, in order to speed up clinical intervention and reduce the risk of chronic complications. Therefore, next-generation DNA sequencing of central genes in the leptin-melanocortin pathway was performed in 1508 children and adolescents with and without obesity, aged 2-19 years. The recruited cohort comprised approximately 5% of the national paediatric population with obesity. The model-estimated effect size of rare variants in the leptin-melanocortin signalling pathway on longitudinal weight gain between carriers and non-carriers was derived. In total, 21 (1.4%) participants had known disease-causing heterozygous variants (DCVs) in the genes under investigation, and 62 (4.1%) participants were carriers of rare variants of unknown clinical significance (VUS). The estimated frequency of potential genetic variants associated with obesity (including rare VUS) ranged between 1/150 (VUS and DCV) and 1/850 (DCV) and differed significantly between participants with and without obesity. On average, the variants identified would result in approximately 7.6 kg (7.0-12.9 kg at the 95th percentile of body weight) (girls) and 8.4 kg (8.2-14.4 kg) (boys) of additional weight gain in carriers at age 18 years compared with subjects without obesity. In conclusion, children with a genetic predisposition to obesity can be promptly identified and may account for more than 6% of obesity cases. Early identification of genetic variants in the LEPR , PCSK1 , POMC , MC3R and MC4R genes could reduce the societal burden and improve the clinical management of early severe childhood obesity and its implementation should be further investigated., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Šket, Kotnik, Bizjan, Kocen, Mlinarič, Tesovnik, Debeljak, Battelino and Kovač.)

Phage display coupled with in vitro affinity selection to mimic evolutionary principles has propelled the discovery of specific binding peptides and proteins for diverse applications, including affinity chromatography. By tailoring screening conditions, ligands with desired predefined properties, such as pH- or ion strength-responsive binding, can be identified from phage-displayed combinatorial peptide libraries. Initial hit peptides can be further optimized through directed evolution by focused mutagenesis and rescreening. Quantitative analysis of eluted binders with next-generation sequencing (NGS) assists in reducing enrichment bias and simplifies picking the most promising ligand candidate(s) through enrichment ranking. We describe, in detail, procedures of ligand selection for affinity chromatography using peptide phage display library screening, focused mutagenesis, and NGS. Furthermore, we outline the subsequent workflow for ligand characterization and affinity column construction., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.)

Recurrent cardiovascular events remain an enigma that accounts for >30% of deaths worldwide. While heredity and human genetics variation play a key role, host-environment interactions offer a sound conceptual framework to dissect the molecular basis of recurrent cardiovascular events from genes and proteins to metabolites, thus accounting for environmental contributions as well. We report here a multiomics systems science approach so as to map interindividual variability in susceptibility to recurrent cardiovascular events. First, we performed data and text mining through a mixed-methods content analysis to select genomic variants, 10 single nucleotide polymorphisms, and microRNAs (miR-10a, miR-21, and miR-20a), minimizing bias in candidate marker selection. Next, we validated our in silico data in a patient cohort suffering from recurrent cardiovascular events (a cross-sectional study design and sampling). Our findings report a key role in low-density lipoprotein clearance for rs11206510 ( p  < 0.01) and rs515135 ( p  < 0.05). miR-10a ( p  < 0.05) was significantly associated with heart failure, while increased expression levels for miR-21 and miR-20a associated with atherosclerosis. In addition, liquid chromatography-mass spectrometry-based (LC-MS-based) proteomics analyses identified that vascular diameter and cholesterol levels are among the key factors to be considered in recurrent cardiovascular events. From a methodology innovation standpoint, this study offers a strategy to enhance the signal-to-noise ratios in mapping novel biomarker candidates wherein each research and conceptual step were interrogated for their validity and in turn, enriched one another, ideally translating information growth to knowledge growth.