Bioinformatics connects life sciences and quantitative sciences, typically involving the application of software and algorithms to solve computationally intensive questions, such as those in genomics, sequence analysis, and systems biology. Questions tagged Bioinformatics should have a direct ...

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0
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5answers
158 views

How much does a typical biologist know about signal processing, machine learning, and (theoretical) computer science? [closed]

How much does a typical biologist know about signal processing, machine learning, and (theoretical) computer science? Coming from a neuroscience background where knowing about algorithms and computer ...
4
votes
3answers
307 views

Does anyone know a good software for producing tanglegrams?

I'm trying to look at relationships between parasite and host phylogenetic trees. I have done a bit of searching for a software in which to do this with, and I have tried using Dendroscope and ...
3
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0answers
41 views

What does the term 'epitope mapping' mean? [closed]

Epitope mapping means identifying the binding site of antibodies on the target antigen. This means that the site to be identified is part of the antigen and not antibody, am I right?
2
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2answers
120 views

How do I perform recurring pattern mining or regular expressions of nucleotide sequences?

I am interested in performing nucleotide sequence pattern-mining (regular expressions) which is 12 characters (sequences) in length from a dataset. Is that possible to script using MATLAB?
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2answers
1k views

Scoring sequence against position weight matrix

I have a weight matrix of length 20 x 15 (amino acids x sequence positions). Each element of my weight matrix is a relative probability If I have a sequence say "AAPGTGASMHSGLLW" how would I score it ...
2
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1answer
55 views

How can I view modENCODE data faster?

I am trying to view several data tracks in the modENCODE GBrowse genomic browser. However, the site is so slow, it is practically unworkable. Is there a faster way to explore the data?
1
vote
1answer
61 views

Genome Assembly Using Reads

I'm taking an online bioinformatics class and I am stuck on a problem. The resources I have found don't help that much. Here is the problem: "Assemble the error-free reads from a circular genome on ...
1
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2answers
304 views

Draw simplified phylogenetic tree for kids

I need to draw simple, phylogenetic tree for kids lecture. I am looking for an online tool where I can enter organisms (e.g., human, wasp, fungus) and get figure of a phylogenetic tree. Tree should ...
1
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1answer
53 views

How to selectively download 3 fields from every record in UniProtKB?

I want to download a comprehensive table of protein names from uniprot.org. More precisely, I want to generate a tab-delimited table consisting of the id ...
3
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1answer
70 views

Regarding the NCBI FTP site

I am trying to extract information about SNP data from the FTP server of NCBI. Could someone please explain to me how the directory is organised? There are many many files and folders and I can't ...
2
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0answers
24 views

How are HSPs identified in UCLUST

I am new in Bioinformatics and recently studying UCLUST algorithm by Robert Edgar(2010). It is a fast sequence searching and clustering algorithm. The algorithm is heuristic based. I studied that ...
2
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2answers
52 views

Hiding identical sequences in NCBI web interface

Sometimes there are identical sequences in Genbank/Genpept, most often coming from the same species but different strains. Ie if I look up "bacteria chitin synthase", the 624-aa protein from Dickeya ...
4
votes
1answer
195 views

What makes a DNA sequence motif a DNA sequence motif?

I've read about DNA sequence motifs, but still don't understand what makes some sequence a DNA sequence motif. Is this a well-defined concept? For, example, What are DNA sequence motifs? says: ...
4
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2answers
459 views

Why is assembling paired end illumina without any input parameters an important problem?

In one of the comments in this question about multiple sequence alignment, it was stated @5heikki: btw if you want a good bioinformatics problem, come up with an assembler that assembles any ...
1
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2answers
89 views

Recommended sequence clustering algorithm for transcriptome data

I'm working on a project where I'm going to analyze a large amount of transcriptome data. After assembling our RNA-Seq reads into contigs using Trinity, it looks like I'm going to have about 10GB of ...
3
votes
2answers
278 views

How to use Autodock just for (re)scoring

I have some protein-ligand complexed that I have been docking with some other software and just want to use Autodock to evaluate those complexes. So, basically I just want to use it as a scoring ...
3
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2answers
90 views

Sequence alignment scoring

The following table is from Deonier's text Computational Gene Analysis at p. 152. This is an exercise in global sequence alignment and scoring of alternative sequences. The text proposed a solution ...
2
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1answer
81 views

Comparing Shine Dalgarno scores, creating a distribution

I am in the process of creating a poster for the phage that I recently annotated. The phage is an A4 and the portion of the poster I am working on is analyzing the data that we have collected. I have ...
2
votes
1answer
67 views

Converting Ensembl Compara gene tree DNA alignment to corresponding amino acid alignment

I have Ensembl compara gene tree alignments (Compara.gene_trees.57.fasta.gz downloaded from ftp://ftp.ensembl.org/pub/release-57/emf/ensembl-compara/homologies/) in nucleotide format. According to ...
1
vote
1answer
66 views

To what extent is it possible to understand if a bacteria can produce a protein? (in silico only!)

I have to answer a question about a sub-task of my thesis: Can the bacteria X produce the protein Y? I searched of course Google and BLAST. There is no data supporting that this specific bacteria ...
4
votes
4answers
3k views

E-value BLAST cut-off

What is the best cut-off for e-value in BLAST? Some say 0.01 ,others 0.0001? Even BLAST tutorials don't give a very clear idea about which cutoff suits which purpose? Could some experts give me a ...
1
vote
1answer
47 views

About the quality of microsatellites

I built a script to detect microsatellites in a FASTA file. However, there are thousands of possibilities. So, my question is: what are the markers of a "good" or "useful" microsatellite? - How ...
3
votes
0answers
140 views

Accuracy of genome size estimation by flow cytometry

I'm working on a genome project and using an in silico k-mer analysis to estimate the size of our genome based on the available Illumina reads. The k-mer based estimate is consistent across a wide ...
1
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2answers
121 views

Heterochromatin binding sites position information

I am working on a project and I'm trying to find data on the position of genes and heterochromatin binding sites such as HP1 in Drosophila melanogaster. Is this information available for the DGRP ...
2
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2answers
103 views

chimeric sequences [closed]

I understand that chimeric sequence identification is done in results of sequencing projects to remove them and improve the quality of the output. I am unsure as to how they show up during sequencing. ...
1
vote
1answer
233 views

Convert gene name to uniprot ID

i have a list of gene name in a file CHRNB2 EGR2 GCK KRT14 LMNA FGF3 TK2 ABCC8 How can I map them to uniprot ID ? P.S I tried Uniprot "ID mapping" ...
0
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2answers
65 views

is there a way to do batch download for all gene pathways?

I would like to download all the gene pathways and genes of each pathway. Preferably, gene length of each gene as well. It would be a lot more convenient if there is an R package.
1
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1answer
45 views

Alleles notation in SNPPedia criteria

I can understand the allele notation when is in the form rs8176719(T;T) or rs8176719(G) but recently i found this ones rs8176719(T;-) or rs8176719(-;T). So im confused, rs8176719(T;-) is the same as ...
1
vote
1answer
80 views

Recombination-based vs. Sequence-based genetic mapping

Now that sequencing is becoming increasingly cheap, what is the value of recombination-based genetic mapping against the sequence-based genetic mapping? I think that in the past recombination-based ...
2
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0answers
56 views

Can a heterozygous allele show non-heterozygous expression in a family?

I'm doing a family study looking for novel cancer-associated variants in germ-line samples; the goal is to find candidate biomarkers which might be used for early detection. At an earlier step our ...
0
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1answer
67 views

Can someone suggest me good opencourseware links for learning computational biology basics?

My internet is slow and I have only 1GB data usage allowed for this month. And I want to make maximum out of it for learning some basics of computational biology. Which are the best online course ...
5
votes
5answers
165 views

What are some examples of evolving networks in biology?

I'm a master student working on networks analysis in general. A network is something that has nodes and there are links between the nodes. Nodes and links could have attributes. An evolving network is ...
2
votes
0answers
177 views

Software to calculate Fst from sequence data

I'm looking for a software to calculate Fst from 3 loci DNA data of individuals from a metapopulation. I don't have any prior on the population structure (have no idea of the number of subpopulations ...
4
votes
1answer
123 views

Blosum matrix with probabilities instead of the positive and negative scores

I am trying to find a version of the BLOSUM matrix that has the frequencies instead of the scaled log-odds. i.e. instead of the common version that tells us that the score LEU/ASP is -4, I would like ...
8
votes
2answers
1k views

How can rooted and unrooted (phylogenetic) trees be distinguished from one another

I understand that both are similar in structure But how can they be easily identified as one or the other? Is it simply based on the presence or lack of a named root (the root is identified as a ...
2
votes
1answer
44 views

Quantitative Comparisons of Phylogenetic trees

I am working on a broad phylogenomic analysis of proteins involved in one particular cellular process. I have constructed a phylogenetic tree for each protein. I am now working on comparing those ...
5
votes
3answers
222 views

Protein structures given in PDB and SNP's

There are millions of proteins given in PDB, the sequence for which we can download in FASTA format. There are also hundreds of SNP's given in NCBI dbSNP. My question is whether the proteins in PDB ...
4
votes
1answer
322 views

The parameter for setting the number of mismatches in standalone blast

In a standalone blast search, is there a parameter that could be specified to fix the number of mismatches allowed in an alignment. I went through the parameters and I could only find parameters to ...
3
votes
1answer
110 views

Should the sum of RPKMs be constant over experiments

I have cufflinks data from 18 different RNA-seq experiments. I've noticed that if the sum all the RPKM values for a particular experiment, are vastly different between experiments. How could this be? ...
2
votes
0answers
40 views

dbSNP database table desciptions

I am trying to build a local implementation of dbSNP. I would like to know the descriptions of tables listed on ftp://ftp.ncbi.nlm.nih.gov/snp/database/organism_data/human_9606 and on ...
1
vote
1answer
49 views

What is the close and related genome used for in Gene models?

all I am a little bit confused about using the related genome or reference genome. When we have a reference genome, we can do alignment. Also we can do the assembly. Can you give some more reason ...
4
votes
1answer
190 views

Local storage of NCBI database in MongoDB [closed]

My short term goal in a project is to build a local database of the NCBI dbSNP database. The data and schema are available on the FTP site(). I was going to implement the database using MySQL, but I ...
2
votes
2answers
89 views

Databases for metabolic pathways of human disease

Which databases contain the metabolic pathway of human diseases? I have searched Metacyc and KEGG but didn't find the appropriate metabolic pathway.
3
votes
1answer
48 views

I2D vs STRING for protein-protein interactions

Can someone clearly explain me the differences between STRING and I2D(Interlogous interaction database) ? What does each database do best ? Which database is better for what kinds of studies etc ?
3
votes
1answer
225 views

What do the Clustal Alignment Symbols Mean?

Occasionally I will run protein alignments on peptide families and I can never remember what the symbols mean to show degrees of identity. What do they mean?
1
vote
1answer
67 views

downloading a reference genome for alignment

I am currently working through the code example on the MATLAB website. It requires me to download the reference genome of Arabidopsis thaliana (thale cress) so I can use BowTie2 to align the Chip-Seq ...
2
votes
1answer
109 views

Steps to confirm if predicted miRNA is good or bad

I aligned all miRNAs available to the supercontigs of a particular genome with certain parameters (e value of 0.01 and a word match of atleast 7 as suggested in this paper). I have also isolated the ...
8
votes
1answer
376 views

List of np-hard problems in biology/bioinformatics

I'm not sure if this is the right place for this but... I am looking for a list of computationally "hard" problems such that if a problem from this list could be solved effectively, it would be ...
2
votes
1answer
155 views

How to determine the direction of regulation of a gene by comparing gene expressions?

I am just learning about the gene expressions and regulation. Several researches focus on finding the genes of altered gene expressions on a microarray to claim that they have a correlation to a ...
1
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0answers
40 views

What is the suitable terminology to describe this study approach?

I need to know the correct term(s) which are usually used in the parlance of both biology and bioinformatics for this study approach: About 11 transcripts were investigated using qPCR for a number of ...