Figure 1.

Study design

30 iPSC clones were generated from early passage endothelial cells (ECs), derived from, in total, 6 neonatal (umbilical vein, hUVEC; cord blood, hCBEC) and 3 aged donors (64–88 years, saphenous vein, hSVEC; peripheral blood, hPBEC). iPSC clones in passages 7–12 were subjected to whole exome sequencing (WES). 3 single cell iPSC clones per donor (in case of donor D#37, 3 clones derived from hSVECs and 3 clones from hPBECs) were included to investigate inter-clonal variabilities. Moreover, for 4 donors, variant frequency in the corresponding parental cell population was determined by WES to discriminate between enrichment of pre-existing variants and de novo mutagenesis during reprogramming. Additionally, AFs of selected variants within parental cell populations were assessed by ultra-sensitive amplicon sequencing.