Conventional sequencing procedures are performed on thousands or millions of cells simultaneously, and the resultant signal is an average signal that obscures cellular heterogeneity. The limitation is surpassed with single-cell sequencing, which sequences the genome or transcriptome of a single cell to find heterogeneity of cells in unprecedented detail.
This technology has revolutionized the biology of cancer, in which tumors are now viewed as heterogeneous populations of cells, and not homogeneous masses. Single-cell RNA sequencing assists in the detection of drug-resistant cells, cancer stem cells, and interactions of immune cells in the tumor microenvironment.
Single-cell sequencing is also developing in the fields of developmental biology, immunology, and neuroscience, in addition to oncology. It has enabled scientists to follow cell differentiation processes, learn about the immune response, and map out complex tissues on a cellular scale.
Even though cost, data complexity, and technical variability are still problems, single-cell approaches are becoming more accessible and scalable due to the rapid technological improvements.
MBH/AB