Chromosomal reciprocal<unk>  of the 4th and 20th chromosome. In genetics, chromosome<unk>  is a phenomenon that results in unusual rearrangement of chromosomes. This includes balanced and unbalanced<unk> , with two main types: reciprocal-, and Robertsonian<unk> . Reciprocal<unk>  is a chromosome abnormality caused by exchange of parts between non-homologous chromosomes. Two detached fragments of two different chromosomes are switched. Robertsonian<unk>  occurs when two non-homologous chromosomes get attached, meaning that given two healthy pairs of chromosomes, one of each pair "sticks" and blends together homogeneously. A gene fusion may be created when the<unk>  joins two otherwise-separated genes. It is detected on cytogenetics or a karyotype of affected cells.<unk> s can be balanced (in an even exchange of material with no genetic information extra or missing, and ideally full functionality) or unbalanced (where the exchange of chromosome material is unequal resulting in extra or missing genes).
Chromosomal translocation
Chromosomal fragile site
Defocus aberration
Germline mutation
Robertsonian translocation
Chromosome instability
Aneuploidy
Copy number variation