The Rand index
I've been looking for ways to compare clustering results and through my searching I came across something called the Rand index. In this short post, I explain how this index is calculated.
Getting started with Arabidopsis thaliana genomics
I have started to work on Arabidopsis thaliana, as I mentioned in my last post. As noted in the Encyclopedia of life: Arabidopsis thaliana is the most widely used model organism in plant biology. Its small genome size, fully sequenced in the year 2000, chromosome number, fast growth cycle (from seed germination to set in...
Read GTF file into R
The Gene Transfer Format (GTF) is a refinement of the General Feature Format (GFF). A GFF file has nine columns: seqname The name of the sequence; must be a chromosome or scaffold. source The program that generated this feature. feature The name of this type of feature, e.g. "CDS", "start_codon", "stop_codon", and "exon" start The...
Getting started with Seurat
Updated 2018 April 11th This post follows the Peripheral Blood Mononuclear Cells (PBMCs) tutorial for 2,700 single cells. It was written while I was going through the tutorial and contains my notes. The dataset for this tutorial can be downloaded from the 10X Genomics dataset page but it is also hosted on Amazon (see below)....
Learning about Snakemake
As promised two years ago, here's a short blog post on Snakemake. I have been using Bpipe to manage my workflows/pipelines but Snakemake has been mentioned to me on more than one occasion; in particular: @davetang31 seems useful if testing many diff types of pipelines. snakemake seems a bit more practical if analyzing many samples...
Deleteriousness versus pathogenicity
What's the difference between deleteriousness and pathogenicity? Box 1 from the article "Guidelines for investigating causality of sequence variants in human disease" has the following definitions:
Incidental findings using GEMINI
The American College of Medical Genetics and Genomics (ACMG) have recommended that genetic variants that may be pathogenic or likely pathogenic in certain genes should be reported back to the patient. The latest list of genes can be found here. How do I assess whether a variant is pathogenic or likely pathogenic? Use this tool,...
Summary plots from GEMINI
I'm a fan of GEMINI and have been using it for for a year and a half for various exome projects. I have written two scripts that can generate variant summaries from a GEMINI database. I prefer bar plots over the pie charts created by VEP. A summary pie chart created by VEP.
Creating a flowchart using R
The diagram package makes it easy to create flowcharts in R. In this post I'll show an example of creating a simple flowchart. The most important part is to understand how the coordinate systems works; once you understand that, it's just a matter of placing your arrows and boxes accordingly to create your flowchart. To...
Gene to OMIM phenotype
A couple of weeks ago, I wrote a post on identifying OMIM phenotypes that are associated with a gene of interest. I thought I solved the problem by using one of my favourite R packages (biomaRt) but alas. For example, I could not find any OMIM IDs associated with the TTN gene using biomaRt. In...