Biology subjects

Kechin, A.

Publications and source records attributed to Kechin, A..

5 recordsLinked to original sources

bioRxiv2026

Genomic Variability of the HCT116 Cell Line Identified Using Oxford Nanopore Sequencing

HCT116 is a colorectal cancer cell line frequently used in anti-tumor drug development experiments as well as in studies of the molecular machinery of eukaryotic cells. It is well characterized by the presence of several single-nucleotide and short mutations in multiple oncogenes and tumor suppressor genes, including KRAS, PIK3CA, MLH1, CTNNB1, CDKN2A, TGFBR2, and BRCA2. However, its landscape of large genomic rearrangements (LGRs) and copy number variants (CNVs) is still far from being fully understood. Therefore, the aim of this study was to identify LGRs and CNVs in several HCT116 cell line samples using Oxford Nanopore sequencing technology, including three samples from the SRA NCBI database, and to compare common and unique variants across all samples. Using the recently developed eLaRodON tool, we identified 22,666 common LGRs, among which more than 70% of tandem duplications and deletions larger than 80 kb were confirmed by CNV analysis. Among LGRs affecting protein-coding sequences, two in-frame rearrangements were identified: a deletion of exons 4-6 and a duplication of exon 10 in the CCSER1 gene, which encodes a cell division regulator protein. Given its high rearrangement rate in various tumors and the clinical significance of its overexpression, this finding may be potentially useful in future research on this cell line. Regarding differences between samples, we found that LGRs in the laboratory sample and in one of the three SRA NCBI samples occurred more frequently via ALR/Alpha repeats than via Alu repeats, in contrast to common LGRs and those unique to the other samples, a finding that may indicate the presence of unique mechanisms of genomic instability. Thus, this study reveals a broad spectrum of large genomic rearrangements and copy number variants that can be identified in the HCT116 cell line using Oxford Nanopore sequencing, including rearrangements specific to distinct cell line samples.

genomics↗

bioRxiv2025

eLaRodON: identification of large genomic rearrangements in Oxford Nanopore sequencing data

Long-read sequencing enables more accurate detection of large genomic rearrangements (LGRs) compared to short-read technologies. However, existing tools for LGR calling continue to evolve and require further optimization. In this study, we present eLaRodON, a novel tool for identifying LGRs in Oxford Nanopore sequencing data. Using publicly available datasets--including Mycobacterium tuberculosis genomes with extensive complete genome references and the human cell line NA12878--we demonstrate that eLaRodON outperforms existing tools (NanoSV, Sniffles2, NanoVar, and SVIM), achieving an AUC of 0.61 (vs. 0.13-0.43) for M. tuberculosis and 0.86 (vs. 0.40-0.72) for the human genome. Validation against gold-standard LGR sets (derived from de novo Flye assemblies and Mauve alignments) confirmed the tools high accuracy. Notably, we identified recurrent false-positive LGR patterns across diverse datasets (M. tuberculosis, NA12878, and {lambda} phage controls). Orthogonal validation by targeted NGS and Sanger sequencing yielded a variant verification rate of 67-100% for different LGR types--including those supported by a single read. These results represent a significant advancement in LGR detection accuracy, with implications for genomic research and clinical applications. eLaRodON is an open-source program, and its code can be freely accessed on GitHub: https://github.com/aakechin/eLaRodON/.

genomics↗

bioRxiv2024

A novel approach for simultaneous detection of structural and single-nucleotide variants based on a combination of chromosome conformation capture and exome sequencing

Effective molecular diagnosis of congenital diseases hinges on comprehensive genomic analysis, traditionally reliant on various methodologies specific to each variant type--whole exome or genome sequencing for single nucleotide variants (SNVs), array CGH for copy-number variants (CNVs), and microscopy for structural variants (SVs). We introduce a novel, integrative approach combining exome sequencing with chromosome conformation capture, termed Exo-C. This method enables the concurrent identification of SNVs in clinically relevant genes and SVs across the genome and allows analysis of heterozygous and mosaic carriers. Enhanced with targeted long-read sequencing, Exo-C evolves into a cost-efficient solution capable of resolving complex SVs at base-pair accuracy. Through several case studies, we demonstrate how Exo-Cs multifaceted application can effectively uncover diverse causative variants and elucidate disease mechanisms in patients with rare disorders.

genomics↗

bioRxiv2023

Expanding the list of sequence-agnostic enzymes for chromatin conformation capture assays with S1 nuclease

This study presents a novel approach for mapping global chromatin interactions using S1 nuclease, a sequence-agnostic enzyme. We develop and outline a protocol that leverages S1 nucleases ability to effectively introduce breaks into both open and closed chromatin regions, allowing for comprehensive profiling of chromatin properties. Our S1 Hi-C method enables the preparation of high-quality Hi-C libraries, marking a significant advancement over previously established DNase I Hi-C protocols. Moreover, S1 nucleases capability to fragment chromatin to mono-nucleosomes suggests the potential for mapping the three-dimensional organization of the genome at high resolution. This methodology holds promise for an improved understanding of chromatin state-dependent activities and may facilitate the development of new genomic methods.

molecular biology↗

bioRxiv2020

NGS-PrimerPlex: high-throughput primer design for multiplex polymerase chain reactions

SummaryMultiplex PCR has multiple applications in molecular biology, including developing new targeted NGS-panels. We present NGS-PrimerPlex, an efficient and versatile command-line application that designs primers for different refined types of amplicon-based genome target enrichment. It supports nested and anchored multiplex PCR, redistribution among multiplex reactions of primers constructed earlier and extension of existing NGS-panels. The primer design process takes into consideration formation of secondary structures, non-target amplicons between all primers of a pool, primers and high-frequent genome SNPs overlapping. Moreover, users of NGS-PrimerPlex are free from manually defining input genome regions, because it can be done automatically from a list of genes or their parts like exon or codon numbers. Using the program, NGS-panel for sequencing the LRRK2 gene coding regions was created, and 354 DNA samples were studied successfully with median coverage of 97.4% of target regions by at least 30 reads. Availability and implementationNGS-PrimerPlex is open-source and freely available at https://github.com/aakechin/NGS-PrimerPlex/. Contactaa_kechin@niboch.nsc.ru Supplementary informationSupplementary data

bioinformatics↗