RNA sequencing has become the most frequently used method for the majority of researchers conducting gene expression profiling. However, it is difficult to obtain a complete picture of the transcriptome because short reads cannot accurately assemble complex transcripts.

Isoform Sequencing (Iso-seq) developed by Pacific Biosciences (PacBio), is based on long-read sequencing technology. The unique long-read sequencing feature allows this method to identify new isoforms with extraordinary precision. The Iso-Seq application generates full-length cDNA sequences — from the 5’ end of transcripts to the poly-A tail — eliminating the need for transcriptome reconstruction using isoform-inference algorithms. The Iso-Seq method provides accurate information about alternatively spliced exons and transcriptional start sites. It also reveals information about poly-adenylation sites for transcripts across the full complement of isoforms within targeted genes or the entire transcriptome.