MLPA analysis of sporadic and familial multiple meningiomas. Representative MLPA analyses of a familial multiple meningioma (DAV338, top panel) and a sporadic multiple meningioma (DAV308, bottom panel) are shown with probe IDs on the X-axis. There are 21 MLPA probes for the NF2 gene (one probe for each exon, two probes for the promotor region and one probe on either side of the gene) and 12 control probes located on other chromosomes. The Y-axis shows the relative probe peak height as an indication of copy number. The relative peak heights were calculated by normalizing the peak height of control probes between normal control DNA and tumor DNA. Gray bars indicate the mean peak height with standard deviation from 10 normal control DNAs. Black bars indicate the peak height for the tested tumor DNA. The top panel reveals no deletion of the NF2 gene while the bottom panel is consistent with deletion of one copy of the NF2 gene, including its flanking regions. All multiple meningiomas and a sampling of 10 sporadic solitary meningiomas were tested by MLPA, with results at this locus identical to those from array CGH.