Array-CGH profiles of the DNA of an oncocytoma or clear cell RCC and the respective CNHCs. The DNA of the oncocytoma represents with typical losses at chromosomes 1, 14, 17, 22 and Y (red profile). Array-CGH profile of the DNA of a CNHC-MF cluster (photograph A) reveals a gain of 1p and loss of chromosome 9 (profile A), whereas the profiles of another CNHC-MF cluster (photograph B) and a CNHC-UMF cluster (photograph C) indicated no detectable copy number variations (profiles B and C, respectively). The DNA of the clear cell RCC of patient #16 reveals gains of 1p, 2p, 5q, 17 and a loss of 3p (green profile) commonly observed in clear cell RCC. The array-CGH profile of the DNA of a CNHC-MF (photograph D) of patient #16 is balanced (profile D). All clusters were hematoxylin stained. As a control, the DNA of an isolated pool of 10 leucocytes from blood of a healthy individual showed a balanced genome (leucocyte control). Gains and losses of the X- and Y-chromosomes (green profile, profile A and D) do not reflect true copy number variations. They result from differences between the sex of the reference and the samples DNA (i.e. male patient DNA was hybridized against a female reference DNA thereby resulting in a loss of X and gain of Y chromosome). Bars above the x-axis are considered to be gains, below the x-axis losses of DNA.