Cells grown in vitro, such as induced pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs), are prone to acquiring genetic abnormalities. Long term passaging and the genetic manipulation of cells can cause the development of such aberrations. This can undermine research and lead to misleading results in downstream experiments.
Methods of testing
Karyotyping detects important balanced translocations and as such remains the gold standard of genetic audit required by regulatory agencies and journals. Array analysis is also beneficial as it provides a greater degree of resolution and can identify microdeletions that may be missed by karyotype analysis. Combine both analyses to achieve a comprehensive examination of genomic integrity.
Karyotype vs Array
individual cells note 1
>15-20% of cells
|less than 200 kb
|Copy number detection
|Balanced translocation detection
Note 1 Statistical consideration required. e.g. 20 cell analysis will not always detect 5% mosaicism.