Copy number analysis of CTCs. Array comparative genomic hybridization analysis of (A) 20 CTCs in duplicate (B) and 100 leukocytes (CD45-positive) isolated from the same enriched blood sample from patient #9. The log2 ratio value for each BAC clone is plotted on the y-axis. The x-axis represents the genomic position of each BAC clone on the array, with chromosome numbers indicated. Vertical solid lines indicate chromosome boundaries, and vertical red dashed line represents the centromeric region dividing each chromosome into the p- or short arm (to the left of centromere) and the q- or long arm (to the right of the centromere). Arrows indicate high-level gains on X chromosome region containing AR.