Vector biodistribution. Tissue DNA extracts were assayed for the presence of IDUA sequences by quantitative PCR. Each symbol represents 1 animal. Dashed line indicates the lower limit of detection analyzed from genomic DNA samples collected from heterozygote controls (<0.05). (A) IDUA vector sequences in brain and spinal cord. HP, hippocampus; CB, cerebellum; CTX, cortex; S, striatum; OB, olfactory bulb; THAL, thalamus; SC, spinal cord. (B) IDUA vector sequences in peripheral organs.