This is the dataset used in the benchmarking of ProSolo, a new probabilistic single nucleotide variant caller for single cell DNA sequencing data that provides control over the false discovery rate of different single cell events at genomic sites (e.g. alternative allele presence or allele dropout). It provides the whole exome sequencing data used in assessing ProSolo's performance that is not available elsewhere, namely bulk whole exome sequencing data of a patient with a constitutional mismatch repair defect (MSH6-) and their parents and siblings, a bulk whole exome sample of granulocytes from that patient and 5 single granulocytes whole exome sequenced after whole genome amplification.