TRACE-Seq Reveals Clonal Reconstitution Dynamics of Gene Targeted Human Hematopoietic Stem Cells

We present Tracking Recombination Alleles in Clonal Engraftment using sequencing (TRACE-Seq), a novel methodology that utilizes barcoded rAAV6 donor template libraries, carrying either in-frame silent mutations or semi-randomized nucleotide sequences outside the coding region, to track the in vivo lineage contribution of gene targeted HSPC clones. By targeting the HBB gene with a rAAV6 donor template library consisting of ~20,000 possible unique exon 1 in-frame silent mutations, we track the hematopoietic reconstitution of HBB targeted myeloid-only, lymphoid-only, and multi-lineage repopulating human HSPC clones in immunodeficient mice. Trace-seq barcode fractions of CD34+ cord blood cells before and after engraftment in mice.