Robertsonian Translocation

Robertsonian translocation (ROB) is a common form of chromosomal rearrangement that in humans occurs in the five acrocentric chromosome pairs, namely 13, 14, 15, 21, and 22. Other translocations occur but do not lead to a viable fetus. They are named after the American biologist William Rees Brebner Robertson Ph.D. (1881–1941), who first described a Robertsonian translocation in grasshoppers in 1916. They are also called whole-arm translocations or centric-fusion translocations. They are a type of chromosomal translocation.

A Robertsonian translocation is a type of nonreciprocal translocation involving two homologous (paired) chromosomes or non-homologous chromosomes (i.e. two different chromosomes, not belonging to a homologous pair). A feature of chromosomes that are commonly found to undergo such translocations is that they possess an acrocentric centromere, partitioning the chromosome into a large arm containing the vast majority of genes, and a short arm with a much smaller proportion of genetic content. During a Robertsonian translocation, the participating chromosomes break at their centromeres and the long arms fuse to form a single chromosome with a single centromere. The short arms also join to form a reciprocal product, which typically contains nonessential genes and is usually lost within a few cell divisions.

Read more about Robertsonian Translocation:  Consequence

Other articles related to "robertsonian translocation, robertsonian translocations, translocation":

Robertsonian Translocation - Consequence
... In humans, when a Robertsonian translocation joins the long arm of chromosome 21 with the long arm of chromosome 14 (or 15), the heterozygous carrier is phenotypically normal because there are ... About one in a thousand newborns has a Robertsonian translocation ... The most frequent forms of Robertsonian translocations are between chromosomes 13 and 14, 14 and 21, and 14 and 15, and occur when the long arms of two acrocentric chromosomes fuse at the centromere and the two ...
Down Syndrome - Genetics - Robertsonian Translocation
... that causes Down syndrome may be due to a Robertsonian translocation in the karyotype of one of the parents ... A person with such a translocation is phenotypically normal ... Translocation Down syndrome is often referred to as familial Down syndrome ...