title: Few single nucleotide variations in exomes of human cord blood induced pluripotent stem cells.
abstract: The effect of the cellular reprogramming process per se on mutation load remains unclear. To address this issue, we performed whole exome sequencing analysis of induced pluripotent stem cells (iPSCs) reprogrammed from human cord blood (CB) CD34(+) cells. Cells from a single donor and improved lentiviral vectors for high-efficiency (2-14%) reprogramming were used to examine the effects of three different combinations of reprogramming factors: OCT4 and SOX2 (OS), OS and ZSCAN4 (OSZ), OS and MYC and KLF4 (OSMK). Five clones from each group were subject to whole exome sequencing analysis. We identified 14, 11, and 9 single nucleotide variations (SNVs), in exomes, including untranslated regions (UTR), in the five clones of OSMK, OS, and OSZ iPSC lines. Only 8, 7, and 4 of these, respectively, were protein-coding mutations. An average of 1.3 coding mutations per CB iPSC line is remarkably lower than previous studies using fibroblasts and low-efficiency reprogramming approaches. These data demonstrate that point nucleotide mutations during cord blood reprogramming are negligible and that the inclusion of genome stabilizers like ZSCAN4 during reprogramming may further decrease reprogramming-associated mutations. Our findings provide evidence that CB is a superior source of cells for iPSC banking.
authors.affiliation: Department of Medicine, Loma Linda University, Loma Linda, California, United States of America.
authors.forename: Rui-Jun
authors.initials: RJ
authors.lastname: Su
authors.forename: Yadong
authors.initials: Y
authors.lastname: Yang
authors.forename: Amanda
authors.initials: A
authors.lastname: Neises
authors.forename: Kimberly J
authors.initials: KJ
authors.lastname: Payne
authors.forename: Jasmin
authors.initials: J
authors.lastname: Wang
authors.forename: Kasthuribai
authors.initials: K
authors.lastname: Viswanathan
authors.forename: Edward K
authors.initials: EK
authors.lastname: Wakeland
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Fang
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Zhang
mesh_terms: D000818:Animals; D054337:Cell Dedifferentiation; D002478:Cells, Cultured; D018920:Coculture Techniques; D004252:DNA Mutational Analysis; D059472:Exome; D005312:Fetal Blood / Q000166:cytology*; D042822:Genomic Instability; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000502:physiology* / Q000637:transplantation; D000090062:Kruppel-Like Factor 4; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D016366:Open Reading Frames; D017354:Point Mutation; D044968:Regenerative Medicine; D013724:Teratoma / Q000473:pathology