Figure 1.

Technological assay overview. DNA template molecules and degenerated barcoding oligonucleotides are encapsulated into droplets to contain one or zero of each molecule. Primers are added to enable amplification of each component in parallel until a critical concentration is reached, facilitating interaction between the two clonally amplified PCR products. A barcode sequence exclusive to each droplet is thereby coupled to each target loci from the original template molecule. After emulsion breakage the target products are enriched and prepared for sequencing. Read pairs then undergo barcode-based clustering and prevalent variations are called to produce a set of alleles for each sample ID (as determined by an ID-tag at the 5΄ end of template molecules and target 1 amplicons).