Genetic marker

A genetic marker or molecular marker is a segment of DNA with an identifiable physical location (locus) on a chromosome and whose genetic heritage can be traced. A marker may be a gene, or it may be some section of the DNA with no known function. Because segments of DNA that lie contiguous on a chromosome tend to inherit together, markers are often used as indirect ways of tracing the hereditary pattern of a gene that has not yet been identified but whose approximate location is known. Markers are used for genetic mapping as the first step in finding the position and identity of a gene.

They are widely used in human, plant, animal and microbial genetics. They allow to show variations (polymorphisms) in the DNA sequence between two individuals, modify their phenotype or not. They act as pointers of different regions of the genome.

Types of genetic markers Protein based Based on DNA Bibliography

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