The following table summarizes symbols and abbreviations used in cytogenetics:[1] [2]
| Symbol | Description |
|---|---|
| , | Separates modal number (total number of chromosomes), sex chromosomes, and chromosome abnormalities |
| - | Loss of a chromosome |
| Grouping for breakpoints and structurally altered chromosomes | |
| + | Gain of a chromosome |
| Separates rearranged chromosomes and breakpoints involving more than one chromosome | |
| / | Separates cell lines or clones |
| // | Separates recipient and donor cell lines in bone marrow transplants |
| del | Deletion |
| der | Derivative chromosome |
| dic | Dicentric chromosome |
| dim | diminished signal intensity |
| dn | de novo (not inherited) chromosomal abnormality |
| dup | Duplication of a portion of a chromosome |
| enh | enhanced signal intensity |
| fra | Fragile site (usually used with Fragile X syndrome) |
| h | Heterochromatic region of chromosome |
| i | |
| idic | Isodicentric chromosome (duplication & inversion of centromere-containing segment) |
| ins | Insertion |
| inv | Inversion |
| .ish | Precedes karyotype results from FISH analysis |
| mar | Marker chromosome |
| mat | Maternally-derived chromosome rearrangement |
| p | Short arm of a chromosome |
| pat | Paternally-derived chromosome rearrangement |
| psu dic | pseudo dicentric - only one centromere in a Dicentric chromosome is active |
| q | Long arm of a chromosome |
| r | Ring chromosome |
| t | Translocation |
| ter | Terminal end of arm (e.g. 2qter refers to the end of the long arm of chromosome 2) |
| tri | Trisomy |
| trp | Triplication of a portion of a chromosome |