What is a polymorphism in a gene?

Genetic polymorphism is defined as the inheritance of a trait controlled by a single genetic locus with two alleles, in which the least common allele has a frequency of about 1% or greater. Genetic polymorphism is a difference in DNA sequence among individuals, groups, or populations.

What polymorphism means?

‘Polymorphism’ is a special aspect of ‘genetic variation’, and both terms are often used interchangeably in the literature. It refers to the presence in the same population of two or more alternative forms of a distinct phenotype such as flower color.

How do you detect gene polymorphism?

Commonly used genotyping methods include gel electrophoresis-based techniques, such as polymerase chain reaction (PCR) coupled with restriction fragment length polymorphism analysis, multiplex PCR, and allele-specific amplification.

Why is genetic polymorphism important?

Genetic polymorphisms can contribute to phenotypic differences amongst individuals, including disease risk and drug response. Characterization of genetic polymorphisms that modulate gene expression and/or protein function may facilitate the identification of the causal variants.

Does polymorphism mean mutation?

A mutation is defined as any change in a DNA sequence away from normal. This implies there is a normal allele that is prevalent in the population and that the mutation changes this to a rare and abnormal variant. In contrast, a polymorphism is a DNA sequence variation that is common in the population.

What is the difference between a mutation and a polymorphism?

What are the three classes of DNA polymorphisms?

DNA polymorphisms include: (1) RFLP – restriction fragment length polymorphism; (2) VNTR – variable number of tandem repeats; (3) SSR – simple sequence repeats or STR – simple tandem repeat, i.e. microsatellites, and (4) SNP – single nucleotide polymorphism.

What is the difference between polymorphism and a mutation?

The main difference between mutation and polymorphism is that mutation is a change in a DNA sequence of the genome of a particular organism whereas polymorphism is a mutation that occurs in more than 1% of a particular population. Mutations can be either hereditary or acquired.

Can polymorphism change the function of a gene?

The majority of polymorphisms are silent, meaning they do not alter the function or expression of a gene. Some polymorphism is visible. For example, in dogs the E locus, can have any of five different alleles, known as E, E m, E g, E h, and e. Varying combinations of these alleles contribute to the pigmentation and patterns seen in dog coats.

What does genetic variation in humans mean?

Human genetic variation is the genetic differences in and among populations. There may be multiple variants of any given gene in the human population ( alleles ), a situation called polymorphism . No two humans are genetically identical.