Figure 2. Complex rearrangements involving PLP1 detected by junction analysis (A) and oligonucleotide array comparative genomic hybridization analysis (B) [22].
(A) A complex duplication of the PLP1 region detected by outward facing polymerase chain reaction. Panel (i) shows the PLP1 region with the positions of the outward facing primers. The structure of the duplicated region is shown in (ii), with an enlargement of the complex junction region in (iii). Two or three bp of microhomology, shown by the letters A, C, G and T, were found at the breakpoint junctions (open arrows). (B) Deletion and duplications found in two patients with Pelizaeus-Merzbacher disease and their carrier mother [24], shown by comparative genomic hybridization. A ∼190-kb deletion is followed by a ∼9-kb segment with no copy-number change, and an interrupted ∼190-kb duplication was detected (i). Panel (ii) shows enlargement of the array revealing interruption of the ∼190-kb duplication. In each horizontal yellow box above, blue lines represent an average of the data points. Red data points indicate copy-number gains, green data points indicate losses, and black data points indicate no copy-number change. The y-axes show relative hybridization; genomic position is on the x-axis. Panel (iii) summarizes the structure based on comparative genomic hybridization where a green box shows the region deleted, red boxes show the regions duplicated, and black lines show regions of no change.