Chromosomes carry an organism’s genes and humans have 46 chromosomes. Chromosome translocation is when a portion of a chromosome moves to another location. Translocations can cause disorders, but balanced translocation is usually harmless. Individuals with balanced translocation have an increased risk of reproductive problems. Multi-Color FISH is a tool used for screening translocations.
A chromosome is a strand of DNA and related proteins that exist in the nuclei of eukaryotic cells and carry the organism’s genes. Human genetic material consists of 46 chromosomes, 23 from each parent. Chromosome translocation refers to the transfer of a portion of a chromosome to another location on the same chromosome or to a location on a non-homologous chromosome. When a chromosomal translocation occurs involving a single chromosome, it is referred to as a translocation. Researches have found that translocations have occurred in evolution, but most translocations do not provide an adaptive advantage for an organism.
Translocations were first observed in the late nineteenth century and were often seen in cancerous tumors, where they have since been shown to be common. Further research has shown a connection between the chromosomal translocation and a variety of disorders. For example, a particular type of chromosomal translocation called a “Robertsonian translocation” occurs frequently in patients with familial Down syndrome. This is different from the more common form of Down syndrome in which the patient has 47 chromosomes due to an extra copy of chromosome 21. Patients with familial Down syndrome often inherited the Robertsonian translocation from a parent who has only 45 chromosomes , but is not affected.
Balanced translocation occurs when pieces of two chromosomes swap places. In balanced translocation, all of the genetic material that should be present is, in fact, present, and the individual will likely not experience any health problems. If a person with a balanced chromosome translocation has a child and only one of the chromosomes is passed on with the translocation, the child will be missing some genetic material and will have three copies, rather than two, of other material. This is called an unbalanced translocation.
The balanced chromosome translocation is estimated to occur in one in 625 individuals. While these individuals are likely healthy, they are at an increased risk of encountering a variety of reproductive problems, including miscarriage, stillbirth, infertility, and delivering a baby with birth defects . Genetic counseling and testing can help determine what the situation is.
One investigative tool for screening translocations is called Multi-Color Florescence In Situ Hybridization (Multi-Color FISH), also known as spectral karyotype. It is used for cancer diagnosis and can show small translocations that would otherwise not be seen. Giemsa-stained karyotypes are another analysis tool.
Protect your devices with Threat Protection by NordVPN
