Methods to distinguish masked hypodiploidy from high hyperdiploidy in ALL
| Method . | Masked hypodiploidy . | High hyperdiploidy . |
|---|---|---|
| Cytogenetics | Only tetrasomies (rare single trisomies) | Mainly trisomies, some tetrasomies |
| Interphase FISH | Two clones: one with monosomies and disomies and one with disomies and tetrasomies | One clone with disomies, trisomies, and tetrasomies |
| DNA indexing | Hypodiploid plus hyperdiploid G1/G0 peaks | Hyperdiploid G1/G0 peak |
| SNP array analysis | Gained chromosomes (tetrasomies or rarely trisomy) have retained heterozygosity; all remaining chromosomes display complete LOH | Gained chromosomes (mainly trisomies; some tetrasomies) have retained heterozygosity; the majority of other chromosomes also have retained heterozygosity (occasionally LOH for single chromosomes) |
| Method . | Masked hypodiploidy . | High hyperdiploidy . |
|---|---|---|
| Cytogenetics | Only tetrasomies (rare single trisomies) | Mainly trisomies, some tetrasomies |
| Interphase FISH | Two clones: one with monosomies and disomies and one with disomies and tetrasomies | One clone with disomies, trisomies, and tetrasomies |
| DNA indexing | Hypodiploid plus hyperdiploid G1/G0 peaks | Hyperdiploid G1/G0 peak |
| SNP array analysis | Gained chromosomes (tetrasomies or rarely trisomy) have retained heterozygosity; all remaining chromosomes display complete LOH | Gained chromosomes (mainly trisomies; some tetrasomies) have retained heterozygosity; the majority of other chromosomes also have retained heterozygosity (occasionally LOH for single chromosomes) |
FISH, fluorescence in situ hybridization; SNP, single-nucleotide polymorphism.