Due to their unique cellular features, pluripotent stem cells (PSCs) acquire chromosomal aberrations at a rather high frequency during their growth in culture. Analysis of chromosomal integrity should be routinely performed and usually is done at the DNA level of the cells. RNA sequencing (RNA-Seq) has recently become the basic tool for transcriptional studies. Therefore, methods that utilize this already available data to inspect the genomic integrity are very valuable. In this chapter, we provide a practical guide to implement methods of detection of chromosomal aberrations, which are based on RNA-Seq data. The expression-based karyotyping (e-Karyotyping) method is based on global gene expression analysis, while the expressed-SNP-karyotyping (eSNP-Karyotyping) method is based on changes in the ratio between alleles.
Keywords: Allelic bias; Allelic variation; Chromosomal aberrations; Cytogenetics; Gene expression; Pluripotent stem cells; RNA sequencing.