Test Systems Without a Chromosome 17 Centromere Signal to Enumerate

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Test Systems Without a Chromosome 17 Centromere Signal to Enumerate

For a test system that does NOT have a chromosome 17 centromere signal to enumerate:

  • Normal HER2 gene copy number is defined as an average of fewer than four copies of HER2 gene per nucleus for systems without an internal control probe.
  • Amplified HER2 gene copy number is defined as 4 to 6 gene copies/nucleus for test systems without internal control probe.