Chromosomal translocation

Chromosomal translocation is a genetic phenomenon that involves the rearrangement of parts between nonhomologous chromosomes. It is a type of chromosomal abnormality or mutation that can lead to various genetic disorders.

Translocation-4-20

Overview

A chromosomal translocation occurs when a segment of genetic material is moved from one chromosome to another, nonhomologous chromosome. This can happen during the process of meiosis, leading to gametes with abnormal chromosome arrangements.

Types of Chromosomal Translocation

There are two main types of chromosomal translocation: reciprocal and Robertsonian.

Reciprocal Translocation

In a reciprocal translocation, segments from two different chromosomes have been exchanged. This type of translocation is usually an exchange of material between nonhomologous chromosomes.

Robertsonian Translocation

A Robertsonian translocation involves the fusion of two acrocentric chromosomes at their centromeres, with loss of the short arms. This results in a single, large chromosome that contains the genetic material from both original chromosomes.

Clinical Significance

Chromosomal translocations can lead to various genetic disorders, depending on the chromosomes involved and the specific genes that are disrupted. Some examples include chronic myelogenous leukemia (CML), which is associated with a reciprocal translocation between chromosomes 9 and 22, and Down syndrome, which can be caused by a Robertsonian translocation involving chromosome 21.

See Also

• Genetic recombination
• Genetic disorder
• Chromosome abnormality