Questions tagged [sequencing]
DNA sequencing is the process of determining the precise order of nucleotides within a DNA molecule.
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Does the Abbott coronavirus test pick up the virus if you are still in the incubation period? [closed]
It seems like Abbott's ID Now test works by detecting the virus directly as opposed to checking for antibodies? If the test result is negative does that mean you don't have the virus? Or does that not ...
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1answer
17 views
Marking opical or PCR duplicates with picard vs. samtools flagstat
I am trying to identify the best library prep method for noninvasive prenatal test samples, to be sequenced with Illumina Novaseq.
One metric that I am evaluating is the number/ percentage of PCR or ...
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1answer
35 views
Overlap in Paired-end Reads for Sequencing?
Regarding Sequencing:
Do/can the paired-end reads have overlaps?
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1answer
43 views
Location of Reads in Sequencing
I have questions regarding sequencing:
Are paired-end reads from different stands?
What about single reads, are they coming from both strands?
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1answer
28 views
Warning in fastqc
I am checking the quality control of my sequences using the Fastqc tool. For some steps, like "Per base GC content", etc., I received a warning. So, I was wondering whether I Should also take care of ...
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1answer
27 views
Per Base Sequence Content in fastqc
I have a question regarding "Per Base Sequence Content" plot for "fastqc":
In the fastqc documentation, it is written: "In a random library you would expect that there would be little to no ...
2
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1answer
34 views
Translating a genome sequence into possible frames
I have a sequence below from MYC gene about which I need to translate the sequence in all possible frames AND identify (for each frame) which codons are actually used in MYC
...
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0answers
22 views
What samples can be used for a Mutect2 Panel of Normals
I'm working on calling somatic variants from solid tissue tumors. I have one normal and one tumor sample for each patient. I plan to use Mutect2 to call somatic variants after preprocessing the data ...
2
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2answers
47 views
Importance of Proper Pairs vs Aligned Reads for RNASeq data
I have stranded, paired end RNASeq reads that I have aligned using STAR. I plan do conduct a differential expression analysis with DESeq2. After running quality control checks, a good portion of my ...
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1answer
45 views
How can i get data set of illness and not illness people?
I'm new to bioinformatic .. i'm reading a paper and what i got that they made a classification for the people if they have a sequence of a disease or not ...
...
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2answers
1k views
A new paper suggests the Corona Virus has “Uncanny similarity of unique inserts in the 2019-nCoV spike protein to HIV-1” - What does this mean?
Quote:
We found 4 insertions in the spike glycoprotein (S) which are unique to the 2019-nCoV and are not present in other coronaviruses. Importantly, amino acid residues in all the 4 inserts have ...
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103 views
Using BaseRecalibrator in GATK4
GATK4's BaseRecalibrator uses a list of known variants to adjust the base quality scores in a BAM file. I would like to visualize the pre and post recalibration ...
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0answers
18 views
probability of an entire sequence, not just one value
I am reading "Statistical methods in bioinformatics"
I came across this formula:
As explained in the book O are the observations:
My question is why the author ...
149
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4answers
80k views
Why does the Wuhan coronavirus genome end in aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa (33 a's)?
The Wuhan coronavirus's genome was released, and is now available on Genbank. Looking at it...
...
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1answer
50 views
Interpreting MultiQC plot of GATK BaseRecalibration data?
I'm using GATK4 to build a somatic variant calling pipeline. The pipeline uses MultiQC to aggregate quality control data, and one of the QC measures reported is base quality score recalibration from ...
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0answers
21 views
What kind of error-correction code is used in the error-correction code DNA sequencing?
In 2017, Chen et al reported a DNA sequencing technology called error-correction code (ECC) sequencing [1]. They borrowed ideas from communication and coding theory and encoded information redundency ...
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1answer
87 views
Any user friendly way to find rare mutations in whole genome raw?
Is there any user friendly way to find rare mutations in the individual human whole genome sequencing raw data? (from Dante, 30x coverage).
To be more specific, I want to find mutations from this ...
2
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1answer
253 views
Why don't all reads have adaptors?
I got NGS reads back from sequencing platform. I check for adaptors and trimmed them. But I realized only a fraction (eg 30%) have adaptors... why not all of them?
Thanks
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1answer
67 views
Low Fraction of usable antibody reads in CiteSeq
we performed a combined gene expression and CiteSeq experiment with the 10x VDJ kit and 20 conjugated antibodies and sequenced on hiseq. I used cellranger to process the sequencing output. The ...
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2answers
399 views
What is 'k' in sequencing?
When a DNA sequence is sequenced, I've only ever dealt with A,T,C,G and N which indicates un-identifiable bases. However, I came across a 'k' recently and I had asked another researcher who gave me an ...
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2answers
64 views
What is a read count?
A very basic question: What exactly is a read count in shotgun sequencing and how is it calculated? I'm particularly interested in understanding the definition of the read count in the context of ...
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0answers
10 views
How to confirming exon shuffling from genomic sequence, promoter sequence, and mRNA sequence?
I have the genomic sequence, promoter sequence, and mRNA sequence for a novel gene. It is thought that the gene is derived from exon shuffling of multiple genes. How do I characterize each of the 3 ...
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1answer
54 views
CRISPR/Cas9 screen analysis with Mageck: paired-end sequencing
I want to analyse data from a CRISPR/Cas9 screen (control vs. treatment) and I'm using Mageck (https://sourceforge.net/projects/mageck/). The problem is that I'm working with paired-end sequencing ...
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1answer
84 views
Sequencing center returns data in several files
We send some samples to sequence and we got several (fastq.gz) files for each sample. The files are distributed at two or three folders with different dates (more than a week apart). The dates of the ...
2
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1answer
86 views
Coverage required
I was came across a problem during an exercise in a book and I don't really know how to solve it. I feel like something's missing.
"coverage, c = $NL/G$ (N=number of reads, L=read length, G=genome ...
2
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2answers
68 views
How to best detect the “peaks” in RNA-seq data that are not assigned to any gene?
I encountered that many reads from single-cell RNA seq data were lost in the analysis because not assigned to any gene (genome: galgal6). I am trying to find an approach than could give me all the "...
3
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0answers
70 views
High percentage of poly A sequences in 10X chromium R2 read
I'm currently analyzing two samples of eosinophil cells isolated from mouse lung and the samples are of very different quality.
According to the Cell Ranger summary 56% of the reads can be mapped to ...
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2answers
1k views
What is the name of this type of figure?
This figure comes from this wiki page.
I googled "gene location figure" and "gene location plot", none gets similar results. I also tried search by image, none of the results is close.
so, what is ...
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1answer
75 views
How to reproduce this specific sequence logo from 10 000 human mRNAs?
this is A sequence logo showing the most conserved bases around the initiation codon from 10000 human mRNAs.
I would like to reproduce this sequence logo. How can I get the sequences? which database ...
0
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1answer
59 views
Is there a convention or standard of the highest bits in a sequence logo? [duplicate]
In bioinformatics, a sequence logo is a graphical representation of the sequence conservation of nucleotides (in a strand of DNA/RNA) or amino acids (in protein sequences).
wiki says
The total ...
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1answer
58 views
what does a sequence look like before alignment?
I am confused with Sequence alignment, which is
a way of arranging the sequences of DNA, RNA, or protein to
identify regions of similarity that may be a consequence of
functional, structural, ...
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1answer
314 views
How to compute the Shannon entropy for a strand of DNA?
I'm confused by the computation of sequence logo. Wikipedia gives a process about this without a concrete example.
Let's just consider DNA, so there are 4 bases (nucleic acids).
The following data ...
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1answer
101 views
Why do ten rows (Figure_1) correspond to 2 bits (Figure_2) in a sequence logo?
Following this question, I'm confused with the computation of sequence logo
Following data comes from the book "Machine Learning - A Probabilistic Perspective (Figure_1)"
here is the corresponding ...
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1answer
180 views
What is “aligned sequences” and “consensus sequence” in the context of sequence logo? How to compute these?
In bioinformatics, a sequence logo is a graphical representation of the sequence conservation of nucleotides (in a strand of DNA/RNA) or amino acids (in protein sequences).
so, What is "aligned ...
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1answer
256 views
Paired end sequencing with R1 and R2 of different length. Possible?
There are commercial sequencing kits/sequencers that allow for paired end sequencing in which the two reads obtained for each fragment are of different length?
For example 150bp for R1 and 50bp for ...
3
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2answers
80 views
Produce a single sequential FASTA sequence out of BAM
I'm having problems properly looking for a solution because I'm a layman in Bioinformatics not familiar with the terminology. I'm hoping you can nudge me in the right direction, please! Thank you very ...
3
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1answer
77 views
Mixcr batch processing
I have a folder with 150 pairs of fastq files from an illumina sequence run. I need to precess them with mixcr, how can I do this in a batch with a single command?
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1answer
126 views
Crossover question from Coding Theory
I have a model that, for a given bit of code will produce a binary string. An example is given 01010101, it might produce {1,11}, and given 01010000, it may produce {2, 11}.
I have a lot of these ...
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3answers
41 views
Genotyping technologies do not maintain phase?
Why exactly does genotyping not maintain phase? I guess I'm more confused on what's the difference between sequencing and genotyping, and as a result how phase is maintained in one, but not the other. ...
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2answers
85 views
Short reads vs long reads with regards to break points
My professor in class said the following statements.
Short reads can map break points
Long reads can disambiguate repeat related issues
I'm very new to genomics, so I don't quite understand the ...
3
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3answers
125 views
Tools for quality trimming at 5 prime?
I'm looking for a tool that is capable to do quality trimming at 5' end and it is configurable. For example, I can choose the quality trheshold, the read length, etc. Any recommendations?
I'm ...
3
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1answer
603 views
Significance and timing of “mux scans”
I'm using MinIONQC to do quality control on some ONT data. The software plots several read characteristics over time (hours passed during the sequencing process). These plots contain several vertical ...
4
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1answer
61 views
Are there any Genome in a Bottle-like resources for non-humans (especially for invertebrates)?
Genome in a Bottle is an excellent resource that provides many types of DNA and RNA sequencing reads for a single individual/cell line to test genome assembly and analysis tools. For example there are ...
3
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2answers
119 views
Separation of mixed plasmid DNA sequences post whole-plasmid sequencing
Imagine a DNA sample containing a mixture of different intact plasmids. These samples are sequenced using either MiSeq or HiSeq sequencing. Would it possible to assemble these plasmids post-sequencing ...
0
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1answer
122 views
Where to Download Cancer Raw Reads (fastq)?
Does anyone know where I can download cancer raw reads (fastq files), tumor and Germline for non-humans?
I wanted to make a study with human data but I don't have the control access to download raw ...
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2answers
187 views
How to cluster the human genes by pathways/system-biology/metabolic properties?
I would like to make a chord plot from my data. I have a list of genes that according to my experiments are divided into 64 clusters of enrichment pattern.
I would combine my 64 clusters with a ...
4
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1answer
454 views
Why do I get so many insertions from Minimap2 on my Nanopore WGS?
I'm a starting my analysis on nanopore whole genome sequencing. I start my analysis from this popular Github.
The sample I downloaded was WGS for NA12878, so I would assume it's alignment to GRCh38 ...
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2answers
1k views
Hardware Requirements (specs) for Bioinformatics-dedicated desktop [closed]
I know this is a somewhat general or vague question, but I’m interested in your opinions. I must build a desktop for general bioinformatics activities with human genomes. I will work with Python and R ...
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3answers
58 views
How to score how densely bases are distributed along a given oligo?
Suppose I have a short chain string of oligos, and I want to rate them from 0 to 1 based on how clustered the "A"s are in respect to the chain. For example:
...
9
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1answer
570 views
Why does this human bam file only have one copy of each chromosome?
As we know that in human DNA sequence, one copy of chromosome comes from mother's DNA and another copy comes from father's DNA so as to form two copies of each chromosome in human DNA. So, if we ...
