Objectives

Last updated on 2025-09-25 | Edit this page

Explain what RNA-seq is and describe its typical workflow.
Understand why good experimental design is crucial for RNA-seq analysis.
Identify and define key RNA-seq terminology:
Variability
Feature
Biological vs technical replicates
Covariates and confounding variables
Statistical power
Describe strategies to minimise variability and control confounding variables.
Estimate appropriate replicate numbers and sequencing depth for an experiment.
Compare sequencing design choices:
Poly-A enrichment vs ribo-depletion
Single-end vs paired-end reads
Stranded vs unstranded libraries
Understand the role of multiplexing and spike-in controls in RNA-seq.

What is RNA sequencing


RNA-seq is a method of measuring gene expression using shotgun sequencing. The process involves reverse transcribing RNA into cDNA, then sequencing fragments on a high-throughput platform such as Illumina to obtain a large number of short reads. For each sample, the reads are then aligned to a genome, and the number of reads aligned to each gene or feature is recorded.

A typical RNA-seq experiment aims to find differentially expressed genes between two conditions (e.g. up and down-regulated genes in knock-out mice compared to wild-type mice). RNA-seq can also be used to discover new transcripts, splice variants, and fusion genes.