Abstract
The utility of genome editing technologies for disease modeling and developing
cellular therapies has been extensively documented, but the impact of these technologies
on mutational load at the whole-genome level remains unclear. We performed whole-genome
sequencing to evaluate the mutational load at single-base resolution in individual
gene-corrected human induced pluripotent stem cells (hiPSCs) clones in three different
disease models. Single-cell clones gene correction by helper-dependent adenoviral vector
(HDAdV) or Transcription Activator-Like Effector Nuclease (TALEN) exhibited few off-target
effects and a low level of sequence variation, comparable to that accumulated in routine
hiPSC culture. The sequence variants were randomly distributed and unique to individual
clones. We also combined both technologies and developed a TALEN-HDAdV hybrid vector,
which significantly increased gene-correction efficiency in hiPSCs. Therefore, with
careful monitoring via whole genome sequencing it is possible to apply genome editing to
human pluripotent cells with minimal impact on genomic mutational load.