Polymorphism

{
  "id": "MLC-T-ENV-021555",
  "term": "Polymorphism",
  "field": "Environment",
  "definition": "1. One of several forms of a genetic characteristic at a locus in a population. Also, the presence in a population of two or more relatively common forms of a gene, chromosome, or genetically determined trait.\n\n2. Polymorphism involves one of two or more variants of a particular DNA sequence. The most common type of polymorphism involves variation at a single base pair. Polymorphisms can also be much larger in size and involve long stretches of DNA.\n\n3. Natural variations in a gene, DNA sequence, or chromosome that have no adverse effects on the individual and occur with fairly high frequency in the general population.\n\n4. Difference in DNA sequence among individuals that may underlie differences in health. Genetic variations occurring in more than 1% of a population would be considered useful polymorphisms for genetic linkage analysis.",
  "references": [
    "EPA Genetic Diversity as an Indicator of Ecosystem Condition and Sustainability Glossary at http://www.epa.gov/eerd/Glossary-%20Genetic%20Diversity.pdf",
    "National Human Genome Research Institute",
    "NIH Genetics Home Reference Glossary",
    "DOE Human Genome Project Information, Genome Glossary"
  ],
  "url": "https://mlchart.com/terminology/environment/polymorphism/"
}