Somatic mutations are presented in heatmaps with each row representing a
mutation and each column representing a single cell. Single cells are designated
by their tissue section (A-C) and cell number. Cells and mutations were
clustered with Euclidean distance bi-clustering. The colors indicate the
mutation calls after imputation, with red indicating mutant and blue indicating
wild-type. Variant allele frequencies of the identified mutations in bulk
samples from each section are indicated on the right. Both depicted IPMNs have
multiple unique KRAS mutations. The majority of cells in IP27
(A), a gastric-type IPMN with high-grade dysplasia, have p.G12D in
KRAS (as well as p.R201H in GNAS), while a
small subclone lacks these mutations and instead has p.G12R in
KRAS. IP16 (B) represents a gastric-type IPMN (sections A
and B) with an adjacent ductal adenocarcinoma (section C). In this case, the
IPMN contained two unique and mutually exclusive KRAS
mutations, while the cancer had a third KRAS mutation as well
as a unique mutation in TP53.