Blog Archives

Annotating limma Results with Gene Names for Affy Microarrays

January 17, 2012
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Annotating limma Results with Gene Names for Affy Microarrays

Lately I've been using the limma package often for analyzing microarray data. When I read in Affy CEL files using ReadAffy(), the resulting ExpressionSet won't contain any featureData annotation. Consequentially, when I run topTable to get a list of di...

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New Year’s Resolution: Learn How to Code

January 5, 2012
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Farhad Manjoo at Slate has a good article on why you need to learn how to program. Chances are, if you're reading this post here you're already fairly adept at some form of programming. But if you're not, you should give it some serious thought.Gina Trapani, former editor of tech blog Lifehacker, is quoted in the article:“Learning...

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Query a MySQL Database from R using RMySQL

December 15, 2011
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I use this all the time, and the setup is dead simple. Follow the code below to load the RMySQL package, connect to a database (here the UCSC genome browser's public MySQL instance), set up a function to make querying easier, and query the database to ...

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RNA-Seq & ChiP-Seq Data Analysis Course at EBI

December 8, 2011
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I just got this announcement from EMBL-EBI about an RNA-seq/ChIP-seq analysis hands-on course. Find the full details, schedule, and speaker list here.Title: Advanced RNA-Seq and Chip-Seq Data Analysis Course Date: May 1-4 2012 Venue: EMBL-EBI, Hinxton,...

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An example RNA-Seq Quality Control and Analysis Workflow

December 6, 2011
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I found the slides below on the education page from Bioinformatics & Research Computing at the Whitehead Institute. The first set (PDF) gives an overview of the methods and software available for quality assessment of microarray and RNA-seq experim...

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GEO2R: Web App to Analyze Gene Expression in GEO Datasets Using R

November 17, 2011
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GEO2R: Web App to Analyze Gene Expression in GEO Datasets Using R

Gene Expression Omnibus is NCBI's repository for publicly available gene expression data with thousands of datasets having over 600,000 samples with array or sequencing data. You can download data from GEO using FTP, or download and load the data direc...

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I’m Starting a New Position at the University of Virginia

September 8, 2011
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I’m Starting a New Position at the University of Virginia

I just accepted an offer for a faculty position at the University of Virginia in the Center for Public Health Genomics / Department of Public Health Sciences. Starting in October I will be developing and directing a new centralized bioinformatics core ...

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Sync Your Rprofile Across Multiple R Installations

August 15, 2011
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Sync Your Rprofile Across Multiple R Installations

Your Rprofile is a script that R executes every time you launch an R session. You can use it to automatically load packages, set your working directory, set options, define useful functions, and set up database connections, and run any other code you w...

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Friday Links: R, OpenHelix Bioinformatics Tips, 23andMe, Perl, Python, Next-Gen Sequencing

August 5, 2011
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Friday Links: R, OpenHelix Bioinformatics Tips, 23andMe, Perl, Python, Next-Gen Sequencing

I haven't posted much here recently, but here is a roundup of a few of the links I've shared on Twitter (@genetics_blog) over the last two weeks.Here is a nice tutorial on accessing high-throughput public data (from NCBI) using R and Bioconductor.Cloud...

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Scatterplot matrices in R

July 25, 2011
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Scatterplot matrices in R

I just discovered a handy function in R to produce a scatterplot matrix of selected variables in a dataset. The base graphics function is pairs(). Producing these plots can be helpful in exploring your data, especially using the second method below.Try...

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