Chromosomal translocation
In genetics, chromomal translocations are the breaking and inappropriate merging of two different chromosomes.Translocations generally occur between regions of the DNA that are homologous. A number occurs during meiosis, while other occur later in a person's lifetime, leading for example to the formation of the Philadelphia chromosome (translocation from part of the 9th to the 22th chromosome and vice versa).
Other diseases caused by translocations are:
- Cancer - several forms of cancer are caused by translocations; this has been described mainly in leukemia (acute myelogenous leukemia and chronic myelogenous leukemia).
- Infertility (one of the would-be parents carries a balanced translocation, where the parent is asymptomatic but conceived fetuses are not viable).
- Down's syndrome is caused in a minority (5% or less) of cases by a Robertsonian translocation.