Genetic modification

Genetic markers are specific sequences in the DNA that can be identified and used to 'mark' a particular location on a chromosome. They are essential tools in genetic research and genetic engineering, and have a wide range of applications in medicine, forensics, and agriculture.

Definition

A genetic marker is a gene or DNA sequence with a known location on a chromosome that can be used to identify individuals or species. It can be described as a variation (which may arise due to mutation) that can be observed. A genetic marker may be a short DNA sequence, such as a sequence surrounding a single base-pair change (single nucleotide polymorphism, SNP), or a long one, like minisatellites.

Types of Genetic Markers

There are several types of genetic markers, including RFLP (Restriction Fragment Length Polymorphism), AFLP (Amplified Fragment Length Polymorphism), RAPD (Random Amplification of Polymorphic DNA), VNTR (Variable Number Tandem Repeats), STR (Short Tandem Repeats), SNP (Single Nucleotide Polymorphism), and SSR (Simple Sequence Repeats).

Applications

Genetic markers have a wide range of applications. They are used in genetic mapping and DNA sequencing, to locate genes for specific traits, and to track the inheritance of genes in genetic counseling. In medicine, they are used to identify genetic disorders and to develop personalized treatments. In forensics, they are used in DNA fingerprinting to identify individuals. In agriculture, they are used in plant and animal breeding programs to select for desirable traits.

See Also

• Genetic linkage
• Molecular marker
• Genetic variation
• Genome mapping