Questions tagged [nanopore]
Questions specific to nanopore sequencing. For general question about long reads, use tag long-reads instead and for questions about specific sequencer use a specific sequencer tag (i.e. minion, gridion)
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Nanopore sequencing continuation and data merging
I started a run which should last for 72 hours but unfortunately I had power failure and the remaining hours to complete was 31 hours. However, the base calling and bar coding will be done after the ...
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How much memory should I allocate to FastQC for analyzing large nanopore sequencing files?
I'm running a bioinformatics pipeline to analyze large nanopore sequencing files using FastQC. However, I keep running into an OutOfMemoryError. Here's what happens:...
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How can I normalize DNAseq nanopore metagenomics data?
I'm working on antimicrobial resistance (AMR) surveillance in treated water samples using nanopore long-read DNA sequencing analysis. After analyzing my data with the KMA tool (a k-mer read alignment ...
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Normalization and Comparison of AMR Gene Tables from Long-Read Metagenomics Data without Spike-In Controls
I am conducting antimicrobial resistance (AMR) surveillance in water samples using long-read metagenomics (Nanopore sequencing). After analyzing the data with KMA (a k-mer read alignment tool, Clausen ...
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Normalization in Sequence Analysis Research
I am currently engaged in a research project that involves DNA sequence analysis, utilizing nanopore and KMA alignment software (k-mer alignment). As I delve deeper into my research, I am faced with a ...
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Finding insertion in a plasmid
This question was also asked on Biostars
I received a set of Nanopore long reads of a ~3kbp long known plasmid with an unknown insert between 1kbp and 7kbp. Could you suggest a pipeline to assemble ...
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single_to_multi_fast5 does not collect all the single files if the input folder contains mixed types of fast5 files
I have a dataset that contains thousands of mixed multiple and single fast5 files in a non-homogenous folder structure.
The reads and fast5 files are coming from different labs and some labs gave ...
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686
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Nanopore Flongle vs MinION
How do the Oxford Nanopore Flongle flow cells perform compared to the standard MinION flow cells, when it comes to reliability and error rates? I found this comparison article from last year, from ...
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How should I use dorado basecaller to calculate translocation time? Can I change models' config files?
I am trying to use dorado basecaller to process ONT data. I need to make the move table and I am doing it with --emit-move.
...
- 309
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125
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Is my reference sequence too small?
I'm trying to map ONT long reads to a portion of a gene I'm looking at. The region is about 25bp long. When I search for the region in the document it pulls up the sequence in every read but when I ...
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Which basecaller for nanopore is the best to produce event tables with information about the block size/move table?
I previously used albacore version 2.3.1 to make initial move tables, but then I re-squiggle using Tombo version 1.5.1 to fix the errors.
Example of move table produced by albacore, in which all the ...
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How do I measure the proportion of different bacteria in a sample from a high-throughput sequencer?
[this question is based on a question that was asked on Reddit]
I have sequenced some [mostly cell-free] DNA from a sputum sample on a nanopore sequencing machine, and would like to know what is in it ...
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How much does Nanopore cDNA Sequencing Cost?
[this question is based on a question that was asked on Reddit]
We're interested in doing whole-transcriptome cDNA sequencing of 24 mouse cell lines, and are deciding between Illumina and Nanopore ...
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254
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Improving prokaryotic assembly with other contig/scaffold-level data?
I have what at first sight appears to be a high-quality MAG (~10 pieces, high completion%) that I built from a hybrid assembly (Illumina + Nanopore data) from a cyanobacterium.
Workflow:
Quality ...
- 1,017
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469
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Reading a Fast5-file with Python
I am trying to extract data from fast5-file with python 3.9.13 in Ubuntu. I have found a library "fast5_research"(This package comprises an API to HDF containers used by the research groups ...
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Coordinate numbering between forward (+) and reverse (-) strand in Tombo
My question is related to the output of Tombo re-squiggling algorithm on nanopore data.
Given the position/coordinate on one strand (+ or -), I want to find the coordinate of its exact location on the ...
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How can Iso-Seq reverse transcriptase artifacts be avoided?
My end goal is annotate a de-novo assembled genome. When trying to select the best method for transcriptome assembly I read Iso-seq was the preferred method. However other people suggested Nanopore as ...
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Get number of reads with a single, (almost) exact match to the full length of a reference sequence
I can't find an answer to this in previous questions, so hoping someone can help me now.
We have nanopore sequenced a PCR product, and I've filtered our reads to +/- 10 bp of the expected product ...
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377
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How can I generate ASV file from nanopore sequencing data?
I am converting the fast5 file to fastq by using guppy basecaller after that by using kraken2 classified the sequence.
Now I am trying to generate ASV file.
Is this possible to generate ASV file from ...
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What is the contributing factor in single measurements of nanopore sequencing? One base, a k-mer or difference between the base left and entered?
My question is about nanopore sequencing and specifically about the current that is measured by the device in each measurement. The question is:
In each measurement in nanopore sequencing, the change ...
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somatic SNV tool for ONT samples
I'm looking for a tool to call somatic single nucleotide variations on reads from an Oxford Nanopore Technologies (ONT) run.
I have both tumor and normal samples and have already aligned them to a ...
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Tree Building Algorithm that treats gaps as deletions
I'm part of a nanopore sequencing experiment that will sequence several generations of viruses. The intent is to perform directed evolution by putting selective pressure on these viruses and tracking ...
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How can I get the duration of the events in Nanopore?
PacBio has the concept of IPD (InterPulse Duration) which is the time between two detected consecutive sequences in the raw signal. I have been trying to extract this value in the Nanopore, but I ...
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Understanding fast5 format
I would like to reproduce the results on figure 1 from THIS publication.
I downloaded the data and explore it with h5ls and h5dump based on HDF5.
I would like to understand:
...
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Nanopore variant calling
So far I haven't done any variant calling as such. Nanopore I have used for 16s microbiome data.
Now My question/doubt so how do I proceed for nano-pore virus sequencing data
Steps:
I get fast5 files
...
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637
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Polishing PacBio or ONT with Illumina
Which tool would be good to polish PacBio or ONT with Illumina?
Thank you in advance
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How do I tell that a MinION run has finished based on the files produced?
I want to automate some scripts which should run after a MinION run completes. Is there a file which is produced by MinKNOW which will enable me to tell that the run has finished?
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Doing functional enrichment of microbiome data
I have done gene set enrichment analysis which is now straight forward. Such as taking gene set and making a query. For microbiome data it is not that straight forward which I found out.
Step done so ...
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What are some ways to error correct Oxford Nanopore long read sequencing?
I am sequencing long read genomic sequences to assemble MHC region haplotypes in a non model organism using Cas9 Sequencing Kit (SQK-CS9109) using flongle adaptors in the minION from Oxford Nanopore ...
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Detecting SARS-CoV-2 variants from the mixed virus population
I have a fastq file from Nanopore sequencing data that contains reads from both the UK and South Africa variants of SARS-CoV-2.
The variants are identified by three key mutations in the receptor-...
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Oxford nanopore promethion; does guppy3 separate fast5 into pass and fail? If not what does?
just a quick question about fast5 pass fail folders. I have been working under the assumption that the fast5 pass fail folders I was given as raw data from our ONT vendor came from them doing base ...
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Upgrading guppy basecaller on Oxford Nanopore Gridion via PPA
I am trying to update the guppy_basecaller (current version installed is 3.2.10+aabd4ec) on a ONT Gridion device. I am initially trying to update it via the ...
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340
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Nanopore data clarification regarding merging of samples
We had same set of sample ran on nanopore platform twice.
The issue on hand is.
First run was done it was nearly done but the power went off.
Second run was done completely with enough sequencing ...
- 1,854
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ambiguous calls in nanopolish
I am converting scores into frequencies (from nanopolish results) using Nanopore scripts.
The script filters out lots of rows on the premise that reads where ...
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What is the typical host-to-bug DNA ratio found in nanopore sequencing without amplification?
I'm interested in sequencing a human sputum sample using an ONT MinION without performing any type of whole genome DNA amplification or targeted PCR.
Has anyone found a good reference (or anecdotal ...
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Master of Pores Installation Mac OS Mojave 10.14
I'm bit of a newbie with ONT analyses and am having some trouble with the Master Of Pores installation instructions (https://biocorecrg.github.io/master_of_pores/install.html). I've managed to install ...
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Recommended workflow for RNA long read Kallisto-like TPM estimation?
On short reads, Kallisto/Salmon is a standard workflow for measuring RNA transcript counts in TPM. However, when I tried to Google a similar workflow for long reads, it's not clear there is a ...
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nanopore QC measures on fastq file
I am working with virus nanopore sequencing data. I have to remove host genome from the reads. I want to run the QC on the fastq file after host genome subtraction. I have used nanoplot. It is slow. I ...
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Nanopore microbiome data analysis 16s rRNA data
The steps I have done so far:
used guppy to do base calling from fast5 to fastq. In each barcode file I have 1960 fastq files which I have merged.
trimmed the fastq files using NanoFilt
Now what I ...
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515
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snakemake - using output file not explicitly declared as input for subsequent rule
I am writing a snakemake that, up to now should
use raw sequencing reads to produce a draft assembly using canu
use minimap2 to align the raw reads against the draft assembly, generated by canu.
...
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Train a new basecalling model for nanopore?
Basecalling on nanopore requires a machine learning neural network model, for example here
A popular software from Nanopore for it is https://github.com/nanoporetech/taiyaki, which has many people ...
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Program Quality control for data sequencing (nanopore)
Hope all of you are fine. I am wondering if exists a program easy to use that can bring me Basic Statistics of Quality Control from raw data made by MinION device (nanopore).
I have read about ...
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Kallisto for Nanopore?
Although the Kallisto software was designed for RNA, it has also been very reliable in counting selected FASTA sequences in DNA sequencing. For example, given a WGS sample and my FASTA file. Kallisto ...
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852
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nanopore - where to retrieve information from the basecaller used
Where can I find information about the basecaller used in a specific nanopore run (we have a Gridion machine)?
I know already that we have Guppy v. 3.0.3, which I ...
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How do you map nanopore fast5 files?
Is there a best practices for mapping Oxford Nanopore files to a reference?
Is there a tool that can take a tarball of fast5 files and map them directly or do they need to be converted to fastq first?...
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Microbial Classification with 16S Nanopore Data
I have recently been tasked with analyzing a heterogeneous microbial sample composed of 16S data generated on a MinION sequencer, with the goal of assigning taxonomies and calculating respective ...
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489
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BED file from .bam alignment structure
I am using a pipeline from nanopore to detect structural variants (SVs) in a human sample with long-reads sequencing. The first steps of the pipeline are:
index the reference genome with ...
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Nanopore FASTQ header specifications
Is there a specification anywhere for how a Nanopore FASTQ header should be formatted?
I am creating strategies for generating test FASTQ files and would like to ensure I am generating "correct" ...
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Oxford Nanopore mapping Quality and sequencing error
I'm analyzing some Oxford Nanopore sequencing reads, with several articles stating the sequencing error is between 5% and 15%. Since its 1D and not 1D^2 sequencing i would assume the sequencing error ...
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Compare multiple alignment results' aligned bases
I have aligned a nanopore data set to a reference genome with graphmap, minimap2 and BLASR. The alignment results are stored in BAM files.
I would like to do some concordance assessment, looking at ...