Fig. 4

Visualization of chromosomal structure variations. a Chromosome number variation, trisomy as an example. b Chromosomal amplification, more specifically copy number variation of type tandem repeat. c Intrespersed repeat chromosomal amplification. d Interstitial chromosomal deletion, (e) terminal deletion. There are several forms of chromosomal translocations. These include, (f) dicentric translocation, which is a form of interchromosomal translocation, (g) reciprocal translocation, h Robertsonian translocation, (i) paracentric inversion which is also intrachromosomal translocation, and (j) pericentric inversion. k Complex chromosomal variation. Several chromosomal changes are involved in immunological recognition molecule diversification, including (l) immunological receptor gene rearrangement, (m) immunological receptor gene conversion, (n) somatic hypermutation, and (o) class switch recombination. The gene segments are from the left V, D, J and C. There are up to tens of fragments in each segment type. p Isochromosome, (q) ring chromosome. r Telomere length variations, specifically telomere shortening. Note that the sizes of the telomeres in the ends of chromosomes as well as the telomere shortening are exaggerated