PPOX probe set MLPA results. (A). MLPA trace results for the PPOX probe set in patients belonging to VP families A and E, and two normal controls (N1 and N2) used as reference. Peaks corresponding to control probes are labeled (*). On the X-axis at the bottom of the figure the numbers indicate the PPOX exon to which the peak corresponds; P the pilot probe; R the reference probes. Red arrows indicate the deleted probes. (B). Graph showing the analysis results from Excel. Probes on the PPOX gene are ordered according to their location along the gene. Internal reference probes are included and show a ratio value near 1. The ratio values near 0.5 indicate a heterozygous deletion for the corresponding probes.