Linked genes

Linked Genes are genes that are located close together on the same chromosome and tend to be inherited together. This concept is a fundamental aspect of genetic inheritance and plays a significant role in the fields of genetics, genomics, and molecular biology.

Overview

The concept of linked genes was first proposed by Thomas Hunt Morgan in the early 20th century. He discovered that some genes violate the principle of independent assortment, which was first described by Gregor Mendel. Instead of segregating independently, these genes tend to be inherited as a group, indicating that they are physically linked on the same chromosome.

Genetic Linkage

Genetic linkage is the tendency of DNA sequences that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction. Two genetic markers that are physically near to each other are unlikely to be separated onto different chromatids during chromosomal crossover, and are therefore said to be more linked than markers that are far apart.

Linkage Map

A linkage map is a genetic map of a species or experimental population that shows the position of its known genes or genetic markers relative to each other, rather than a specific physical distance along each chromosome. Linkage maps are created by finding the genetic markers that are in linkage disequilibrium.

Linkage Disequilibrium

Linkage disequilibrium (LD) is the non-random association of alleles at different loci in a given population. Loci are said to be in linkage disequilibrium when the frequency of association of their different alleles is higher or lower than what would be expected if the loci were independent and associated randomly.

See Also

• Genetic recombination
• Chromosomal crossover
• Mendelian inheritance
• Genetic marker