Recent advances in single-cell RNA sequencing are producing exciting new insights into cell diversity within different tissues and cancers. Listen in to hear  Dr Gonçalo Castelo-Branco and Dr Amit Zeisel, of the the Department of Medical Biochemistry and Biophysics at the Karolinska Institutet,  discuss these new developments including an investigation of cell diversity within the central nervous system (CNS), the development of technology and applications, as well as exciting insights into oligodendrocyte heterogeneity.