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 ...

learn more… | top users | synonyms (1)

3
votes
1answer
60 views

What is the potential function of ultra-conserved elements in the genome?

If selection pressure results in conservation of DNA sequences, what is the most plausible explanation for the existence of ultra-conserved elements (refs here and here) given that there hasn't been ...
3
votes
1answer
303 views

Difference between “transcriptional activity” and “RNA expression”

I am working with a network object where the nodes are different events in molecular biology. Specifically; Catalytic activity of X, RNA expression of X, GTP-bound activity of X, Kinase activity of ...
3
votes
1answer
109 views

Can compounds be predicted from Polyketide synthases gene clusters?

I've seen a few talks on the subject. From a gene cluster, there is some decent ability to determine which domains contribute to certain functional groups in the final metabolites. It sounds like this ...
3
votes
1answer
444 views

Displaying nucleotide at a single position from RNA-seq reads in a BAM file

How do I display a single nucleotide position from reads in a BAM file? I have been looking at variation using samtools mpileup, but I want to actually just display the nucleotide at the position I am ...
3
votes
1answer
49 views

relative-rate of evolution

I am supposed to calculate the relative rate of evolution of two sequences (human and sheep) with a chicken serving as the outgroup. The sequences are pretty long, so I will just create a short ...
3
votes
1answer
93 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: ...
3
votes
2answers
80 views

Why only heterogeneous SNVs for validation using genotyping arrays?

I am trying to validate the variants I found using whole genome sequencing . The standard practice, I have seen in the two publications below were to check for the number of heterozygous SNPs called ...
3
votes
1answer
79 views

What is a good source for info on disease frequency distribution among age groups?

I need information on the disease frequency distribution among age groups for an Android app I'm building... Hopefully I've come to the right place. Is there a good data source for this? Like a ...
3
votes
1answer
91 views

Superposing DNA

I have a series of protein models with DNA docked. I now want to superpose the DNA on a reference DNA molecule and extract the translational distance applied and the rotation angle used. I can ...
3
votes
0answers
47 views

Comment on the introduction to a bioinformatics paper

I've written a paper about DNA sequence analysis. This paper attempts to use Bayesian modelling for a set of DNA sequences. It will probably end up either in a statistics journal, or, more likely, in ...
3
votes
0answers
86 views

Statistical Coupling Analysis (SCA) to identify coevolved residues: use of ICA

We've begun to try out the SCA Matlab toolbox (latest version) downloaded from Dr. Rama Ranganathan's website, and, following the included tutorials, would like to apply it to our protein family. The ...
3
votes
0answers
44 views

At which step apply a detection filter when preprocessing microarray data? (Before/After normalization, batch effects removal)

I am trying to understand what is the best practice when preprocessing microarray data using a detection filter (on scanner p-value). Suppose I have a microarray dataset that I have to normalize with ...
3
votes
0answers
34 views

Statistics on energy consumption breakdown per biological functions across organisms?

Are there any statistics available on how much energy organisms use for each biological functions (i.e. something similar to the line of "Bacteria spend X% of energy on information processing, Y% for ...
2
votes
2answers
84 views

Consensus codon optimization by organism

Does a public database exist that contains this information? I'm trying to make a simple gene annotation program that will let me input a DNA sequence and then optimize it based on one of these tables ...
2
votes
1answer
124 views

basic programming and bioinformatics [closed]

As a molecular biology graduate student I have decided to learn some basic programming and bioinformatics since everybody says that it is crucial. For example, what would you learn if you need to work ...
2
votes
1answer
97 views

Expanding the SETI initiative to seek intelligent data within DNA sequences?

I've recently read a couple articles dealing with long term data storage, and DNA was suggested as one of the prime candidates for long term storage of digital data additionally, there is this article ...
2
votes
1answer
25 views

Single channel micro arrays

What does single channel microarray mean? When is it used? Thank you for your case in advance.
2
votes
2answers
33 views

RNA secondary structure comparison

Do you know any program which can compare two and more different RNA secondary structures? I need find some (dis)similarities between lots of predicted secondary structures. And create maybe common ...
2
votes
3answers
548 views

Primer design for Gibson assembly

I'm trying to design a primer for Gibson assembly. My gene of interest is on a plasmid, and I want to copy that gene, and put it into a different plasmid. I am unsure how to design my primers for ...
2
votes
1answer
77 views

How to build S16 rRNAs phylogenetic trees?

Here is what I know so far: Multiple copies are present in prokaryotes, but according to a paper by Lukjancenko el al.[1] it is enough to select the most similar ones. There are stem regions in the ...
2
votes
2answers
45 views

Connection between genes and pathways

I am reading about a paper about inferencing pathway information in cancer cells. Authors refer to ERBB2 as a gene and a pathway. I don't have solid biology background. What exactly means when we ...
2
votes
1answer
225 views

What do rs id, allele coded 0 and allele coded 1 mean?

So, for a project I've been working on (different story), I've been looking at the HapMap Project, and their free online files. In their README file, they talk about how for each legend file for each ...
2
votes
3answers
94 views

What biochemical molecule viewer allows for changes in amino acids and resulting tertiary structure?

I am familiar with the Jmol, Rasmol and PyMoL softwares, and was recently introduced to BioBlender. However, I am completely unaware if any of these programs (or others) are capable of loading a .pdb ...
2
votes
1answer
88 views

Confusion related to a term probe-by-background interaction

I was reading a paper related to bioinformatics where it uses the drug response on the cancer cells and the gene expression of the individual cells are studied to find any useful insights. Specially, ...
2
votes
1answer
133 views

One flybase gene number (FBgn), many Affymetrix Id's

I am trying to convert a set of Affymetrix ID's, like this one 143053_at_3745, to Flybase Gene Numbers (FBgn) like this one FBgn0000015. I have downloaded the Flybase file required to do so (as ...
2
votes
2answers
41 views

Bioinformatics : Drawbacks of using ORA(Overlap Analysis)

What do you think are the potential drawbacks/weakness of using ORA to explain distinction between two phenotypes. I identified a few which were the dependencies of DE and the statistical method used ...
2
votes
1answer
343 views

RNA-seq analysis - q-values in cuffdiff

I'm using cuffdiff 2.1.1 to look for differential gene expression between two conditions. Each condition has 2 biological replicates. The results I get look promising from a log fold change ...
2
votes
1answer
98 views

Any tool to align whole genome sequence data to another genome and give exon regions a higher mark?

I want to align WGS data from several mammals to one reference such as the human genome sequence. Since in most cases exons should be conserved and spliced in the same way and introns should vary, I ...
2
votes
1answer
40 views

Confusion related to the DAVID tool

I am trying to use the DAVID tool to do some gene analysis. I have some probe set intensities for some cancer cell lines. I found this link in the DAVID tool http://david.abcc.ncifcrf.gov/tools.jsp. I ...
2
votes
1answer
111 views

How can I compare rates of evolution for two sets of proteins?

I have a list of candidate proteins as the result of my analysis. I am now trying to find various characteristics that they have in common. One of the things I would like to check is if my candidates ...
2
votes
1answer
88 views

How to check if a fastq file has single or paired end reads

I am trying to check if a fastq file has single or paired end reads. How can I achieve this with an error-proof method? I checked wikipedia and MAQ but I want to know if is there a reliable document ...
2
votes
1answer
44 views

Transition/Transversion ratio

I'm taking a bioinformatics class and at this point we are just going over basic stuff about molecular biology. Half of the class is doing reading/research on our own, so there isn't much class time ...
2
votes
1answer
52 views

Mass Spectrometry Terminology

I began reading this paper (http://www.biomedcentral.com/1471-2105/14/56) and had a few questions about mass spectrometry terminology that I couldn't find answers to elsewhere. Consider the following ...
2
votes
1answer
64 views

.Net DNA/Codon Parser

Does anyone know of an .NET (C#,VB.NET, maybe F#) DNA parser? If not I will probably make one, it doesn't seem like it would be hard. My general idea was to generate something that would report the ...
2
votes
1answer
177 views

Molecular Evolution: Mrbayes never stops?

When I use my own data to build Bayesian phylogenetic trees using the software Mrbayes, after many generations, it never reaches stopping status (namely, the average standard deviation of split ...
2
votes
1answer
252 views

Comparing BLAST and the Smith-Waterman algorithm

I've been asked: how does BLAST improve dynamic programming accuracy? I do know that BLAST is based on heuristic approach that approximates the Smith-Waterman algorithm and that the Smith-Waterman is ...
2
votes
1answer
166 views

How to learn DNA Origami

Can you tell me is there any good softwares and tutorials which can be used to learn DNA Origami. I am new to this and want to learn from basics. Advance thanks for your help edited: INSILICO
2
votes
0answers
46 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
0answers
31 views

Book suggestion on computational molecular evolution

I'm currently reading Computational Molecular Evolution by Yang. Can you recommend alternatives to this book? I am finding it to be lacking on conceptual discussion (it's more focussed on the ...
2
votes
0answers
94 views

Good poly-A filtering rules or tools

I am aligning a large number of ESTs. It seems poly-A tails show in many different ways. In addition to occurring at the very end, they can be flanked by the cloning sequence one one end, or have ...
2
votes
0answers
135 views

Software for counting fly eggs

Is there any software that could be used to rapidly (quicker than humans) count the eggs laid by Drosophila on a substrate by placing them under a microscope with a camera attached? The eggs are laid ...
2
votes
1answer
90 views

ChIP-seq and the output of SPP

I have been processing some ChIP-seq data with the R package spp. I looked through the literature (ENCODE uses it) and it seemed that spp is indicated as a good program to use. I have found and ...
2
votes
0answers
133 views

Too few transcripts from transcriptome assembler Oases

I am trying to run Oases for transcriptome assembly. The result is far from expected, so I would like to ask whether I am running it in a right way? Thanks. Here is my running command: ...
2
votes
0answers
209 views

Turn off multithreading in pymol [closed]

By default, pymol seems to grab the number of cores on the system for rendering. How can I force it to only use one core? Motivation: I have a large collection ...
1
vote
1answer
82 views

Generating custom human DNA sequences based on traits such as eye colour?

I'm wondering if it would be possible to create software (unless some already exists, but I couldn't find any) to generate human DNA (the base pairs on the double helix) containing genes representing ...
1
vote
1answer
63 views

Transcribing DNA to mRNA with introns

I have a problem in my bioinformatics class that I thought I was doing right, but someone else is getting a different answer. Here is the problem: Given the following DNA sequence, ...
1
vote
1answer
60 views

Is there a way to see what representations are currently displayed in PyMOL?

I am using PyMol to visualize .pdb protein structures. I show/hide representation a lot, and sometimes I get confused with what representations are currently displayed. So I end up with doing a lot ...
1
vote
2answers
38 views

Are there tools for automatically parsing glycan names into tree structures?

My colleague and I are working on a project involving data produced at a glycan microarray facility. The array data that came back to us were a list of glycan names (in IUPAC condensed format). We ...
1
vote
3answers
45 views

Using PSI-BLAST

I understand that the first BLAST yields almost the same results as blastp. The second time the iterated blast generates different results as it uses different matrix based on our first result. But I ...
1
vote
1answer
99 views

Codon alignment via Python? [closed]

I have pairs of coding DNA sequences which I wish to perform pairwise codon alignments via Python, I have "half completed" the process. So far.. I retrive pairs of orthologous DNA sequences from ...