High-resolution CGH-array analysis. (a) Results of array-based CGH analysis. Normalized log2 signal intensity ratios of the 4044 clones were plotted on the basis of chromosome position. The clones were ordered from the 1p telomere on the left to the Yq telomere on the right. Each dot represents the signal ratio for an individual BAC clone (dots with gains in green and losses in red). Red lines are scale bars indicating log2 signal intensity ratios of +0.25 and −0.25. A log2 signal ratio of 0 represents equivalent copy number in the tumor and normal DNA. (b) Genomic profiles of chromosome 4 from a patient sample (T1). A log2 ratio over 0.25 represents a genomic copy number gain, and a log2 ratio below −0.25 represents a genomic copy number loss. Physical positions (bp) are indicated. Vertical lines indicate the lowest locus of chromosome 4 in the BAC clone containing the FAT gene. Log2 ratio was −0.73 in this BAC clone, suggesting that homozygous loss occurs at the FAT gene locus.