I already order subtelomere probes on many of my patients. Why perform microarray testing instead of FISH with subtelomere probes?
Array CGH offers more comprehensive analysis of the subtelomeric regions and can identify terminal and interstitial deletions, whereas subtelomeric probes only identify terminal deletions. Furthermore, array CGH can help to determine the size of the subtelomere deletion or duplication. The SignatureChip® has on average > 5 Mb of coverage on each subtelomere. In our experience, an estimated 25% of subtelomeric alterations identified through our laboratory have been interstitial and would be missed by conventional subtelomeric probe analysis.
