Translocation is a chromosomal abnormality that is due to a change in position of a chromosomal segment to another non-homologous chromosome of the same nucleus or to another part of it. It is produced by the exchange of segments between two chromosomes without loss of genetic material is called reciprocal or balanced translocation, when it gives rise to monocentric chromosomes.Translocations can be detected cytologically because the structural heterozygote forms a quadrivalent (4-chromosome association) in meiotic prophase. Sometimes they can also be detected by changes in the size of the chromosomes if the exchanged segments are of different lengths.
