Urovision FISH detects aneuploidy in which chromosomes and also loses which locus?

• A. Aneuploidy in 3, 7, and 17 with loss of 9p21
• B. Aneuploidy in 1, 4, and 8 with loss of 9p21
• C. Aneuploidy in 2, 5, and 9 with loss of 9q21
• D. Aneuploidy in 6, 10, and 12 with loss of 9p13

Answer: (A)

UroVysion FISH is built to detect urothelial carcinoma in urine by looking for specific chromosomal abnormalities. It uses probes for the centromeres of chromosomes 3, 7, and 17 to identify aneuploidy (extra copies of these chromosomes), which is a common finding in bladder cancer cells. It also uses a probe for the 9p21 locus, where loss of this region (often involving the CDKN2A tumor suppressor gene) is frequently seen in urothelial tumors. The combination of polysomy for chromosomes 3, 7, and 17 along with loss at 9p21 forms the characteristic pattern this test is designed to detect, making this option the best fit. Other patterns involving different chromosomes or loci aren’t part of the UroVysion panel and wouldn’t reflect the standard assay targets.