In 2013, Nature named single-cell RNA sequencing as Method of the Year, highlighting its importance in exploring cellular heterogeneity. Single-cell sequencing technology isolates individual cells, amplifies genetic material, and sequences it, generating data in a matrix format: each row corresponds to a cell (with a unique barcode), each column to a gene, and the value indicates the expression level of that gene in the cell.
The human genome contains about 3 billion base pairs, of which approximately 1% are protein-coding genes (about 20,000 to 25,000). Single-cell sequencing can analyze individual cells rather than cell populations, thereby revealing cellular heterogeneity in development and disease states, and identifying novel cell types.