11.1 Gene expression

In this class, we’ve mostly discussed variation at the level of DNA sequence. However, variation in gene expression – and how it interacts with genotype data – is an equally important aspect of phenotype diversity.

Measuring gene expression

Sequencing mRNA molecules (RNA sequencing), aligning them to a reference genome, and counting the reads per gene provides us with a proxy for measuring expression level.

Fig. 1 (source). Counting transcript expression from RNA-seq reads.