TWO-PRIMER SEQUENCING FOR HIGH-THROUGHPUT EXPRESSION ANALYSIS

The disclosure provides a method of sequencing a nucleic acid molecule that contains two or more target regions to be sequenced (such as, for example, barcodes). The invention is advantageous for sequencing by synthesis two or more target regions whose combined lengths plus the length of any intermediate sequence exceeds the available read length on a given sequencing platform. The methods of the invention utilize nucleic acid constructs containing at least the following elements: a complement of a first universal primer, a first target sequence, an optional polynucleotide spacer, a complement of a second universal primer, and a second target sequence. A first round of sequencing by synthesis is performed to sequence the first target sequence by elongating the first universal primer. Once the sequence of the first target region is obtained, and before the complement of the second primer is reached, the first round of sequencing is terminated. Thereafter, a second round of sequencing by synthesis is initiated-this time, by elongating the second universal primer, thereby sequencing the second target region.