Representative array CGH profiles of transformed FCL and FCL-derived cell lines.

Data are plotted as the mean log₂ ratio of the triplicate spots for each clone normalized to the genome median log₂ratio. The BAC and P1 clones covering individual chromosomes are shown. (A) Schematic representation of array CGH analysis on chromosome 2 in case IL116. A single-copy gain of a BAC clone in 2p16 containing theREL gene (log₂ ratio + SD, 0.52 + 0.046) is shown in the FCL sample (on the left ideogram). In the posttransformed biopsy (on the right ideogram), amplification of the same gene locus (log₂ ratio + SD, 1.13 + 0.027) is shown. (B) Homozygous deletion of P16 gene locus in 9p21 in triploid OZ cell line. Because this cell line contains a near-triploid karyotype, DNA copy number baseline is above the ratio 0.4 of the clones into 9p21, locus of the P16 gene, showed a log₂ ratio lower than −2, indicating the presence of homozygous deletion sized approximately 5 Mb. FISH using a clone containing the gene confirmed the absence of copies ofP16 in the 3 aberrant chromosomes 9. The homozygous deletion had been reported in diploid OZ cell line using Southern blot analysis.25