Person:

Chapman, Alec

Kindred cells can have different genomes because of dynamic changes in DNA. Single cell sequencing is needed to characterize these genomic differences but has been hindered by whole-genome amplification bias, resulting in low genome coverage. Here we report a new amplification method: Multiple Annealing and Looping Based Amplification Cycles (MALBAC) that offer high uniformity across the genome. Sequencing MALBAC amplified DNA achieves 93% genome coverage ≥1x for a single human cell at 25x mean sequencing depth. We detected digitized copy number variations (CNVs) of a single cancer cell. By sequencing three kindred cells, we were able to call individual single nucleotide variations (SNVs) with no false positives observed. We directly measured the genome-wide mutation rate of a cancer cell line and found that purine-pyrimidine exchanges occurred unusually frequently among the newly acquired SNVs.