Extended Data Figure 3. Analysis of loss of heterozygosity in RNA sequencing samples.

a, Polymorphic sites on chromosome 17 in different hPSCs with mutations in TP53. WIBR3 cells with H193R mutation and H9 cells with both P151S and R248Q mutations show less polymorphism in the distal part of chromosome 17p compared to the proximal part of 17p and 17q. *samples with less than 25 reads. b, Summation of the polymorphic sites in the distal part of chromosome 17p compared to the proximal part of 17p and 17q, divided by the overall frequency of polymorphic sites along chromosome 17. WIBR3 cells with H193R mutation and H9 cells with both P151S and R248Q mutations have a significantly different proportion between the two parts of the chromosome, implying loss of heterozygosity (LOH). Error bars depict SEM, ***p < 0.001. c, A schematic representation of possible allele states of TP53 in cultured hPSCs with all observed mutations depicted. Depending on the percentage of mutant reads in a culture, one can deduce if the culture is homogenous or mosaic for a mutation, and whether, in addition to a point mutation, LOH has occurred in the TP53 locus. MAF, minor allele frequency.