Fluorescence In Situ Hybridization (FISH)

FISH analysis with sequence-specific DNA probes. Assay performed by clinically certified cytogenetic technologists and reviewed by an ABMG-certified director, with results typically available in 10-15 days.

What it detects:

  • Genomic sequence of interest
    • Duplications or deletions >20Kb
    • >2% mosaicism (for example: cultures where >2 of 100 cells are trisomy 12)
    • Chromosomal location of genomic gains
    • Chromosome fusions (breakaparts)

What it doesn’t detect:

  • Changes in regions other than the probe-specific sequence

When to use:

  • To confirm findings and refine breakpoints detected by g-banded karyotyping
  • To confirm findings and localize genomic gains detected by aCGH analysis
  • As a screen for microdeletions/duplications of known targets
  • As a screen for aneuploidies other than X, 8, 12, and 17