Definition of the syntaxes:

Main types of structural changes (first section of the tag):
gain  -- gain of extra copy
del   -- loss of chromosome region
flag  -- breakpoint for all types of aberration


Subtypes of structural aberrations (second section of the tag):
add   -- addition of unknown origin chromosomal material
del   -- deletion
der   -- derivative chromosome
dera  -- derivative chromosome formed by gaining of additional 
         chromosomal material of unknown origin
derd  -- derivative chromosome formed by deletion of some regions
dert  -- derivative chromosome formed by translocation events
dic   -- dicentric chromosomes
dup   -- duplications
dupr  -- inverted duplications
hsr   -- homogeneously staining region
i     -- isochromosomes
idic  -- isodicentric chromosomes
ins   -- insertions
inv   -- inversions
qdp   -- quadruplications
r     -- ring chromosomes
t     -- translocations
tas   -- telomeric associations
trp   -- triplications

Numerical abnormality:
gain  -- an extra copy of normal chromosome presents
loss  -- an copy of (normal) chromosome is missing