RNA profiling

RNA profiling involves various techniques to measure the expression levels of RNA in a sample. Here are some key insights from trusted experts:

1. RNA Sequencing (RNA-Seq) Overview: RNA sequencing, or RNA-Seq, enables the entire transcriptome's analysis, allowing the measurement of RNA levels for each gene in the human genome. Typically, it covers around 20,000 genes, offering comprehensive data on gene activity. This method can provide a detailed expression profile for every gene in a single readout. However, RNA-Seq, particularly single-cell RNA-Seq, often results in sparse data with many genes showing zero counts due to the inability to capture all RNA molecules. This sparsity is a major trade-off, demanding careful consideration of its use versus other modalities like protein profiling 1.

2. Single-Cell RNA Sequencing: Single-cell RNA sequencing (scRNA-seq) advances RNA profiling by measuring RNA expression at the single-cell level, which was previously done using microarrays or bulk RNA-Seq. This technology has evolved from microfluidic methods, where individual cells are isolated into separate wells, to more sophisticated techniques. It allows researchers to study heterogeneity within cell populations, providing insights into the distinct gene expression profiles of individual cells. This is crucial for understanding complex biological systems and diseases at a finer resolution 2.

Both methods have their strengths and limitations, necessitating thoughtful selection based on research goals, resources, and specific experimental requirements.