Figure 5.

Signal patterns of TFE3 split‐apart probes. Renal cell carcinomas associated with Xp11.2 translocation involve several different translocations resulting in gene fusions of the TFE3 gene with various fusion partners. The break‐apart FISH assay uses probes both upstream (yellow) and downstream (red) to TFE3 showing different signal patterns in female (A) and male (B) patients. A positive result in a female patient shows a fused or closely approximated normal yellow‐red signal pair (uninvolved X chromosome) and either a pair of split‐apart signals or a single yellow or red signal due to section truncation artifact. Because males have only one X‐chromosome, a positive result in a male patient consists either of a pair of split‐apart yellow and red signals, or of a single yellow or red signal due to section truncation.