Chaos Reign Acadamy (Studies of Everything) : Forum : Mutants (And Mutations)

Mutants (And Mutations)

17 Years Ago

A mutant is an individual, organism, or new genetic character arising or resulting from an instance of mutation, which is a sudden structural change within the DNA of a gene or chromosome of an organism resulting in the creation of a new character or trait not found in the wildtype. In an organism or individual, the new character or trait may or may not be trivial, may occasionally be beneficial, but will usually result in either a genetic disorder or have no phenotypic effect whatsoever. The natural occurrence of genetic mutations is integral to the process of evolution. A more general term for mutant is sport, which includes individuals who vary from type due to mutation, as well as those who vary from type due to other reasons.
Developmental abnormalities not due to genetic change, are frequently referred to as mutants by non-experts. The difference between a developmental abnormality and a mutation is that the former is non-hereditable as the DNA is unchanged. Such abnormalities include extra limbs and occur when a genetically normal embryo develops abnormally.
Occasionally, a body cell in a healthy organism may acquire a mutation caused by a genetic error occurring during routine cell division. This is also known as a "somatic mutation." Such an error may result in cancer.
Creatures with visibly obvious mutations are often regarded as objects of curiosity. Examples include rare blue lobsters. albinos of many species and animals with extra digits. A well-known mutation in fruit flies causes the flies to have legs in place of antennas.An American aquarium even displays what it calls a "double mutant" snake that is both albino and has two heads[6], though calling this a double mutation is a misnomer as the two-headed condition is a developmental abnormality and not a genetic mutation.
Similarly striking human mutations also occur occasionally. People who are completely covered in a fur-like coat of hair are one example (see hypertrichosis). There are also cases of newborn babies having an extended tailbone or a sixth finger. Purely internal, less obvious mutations are more common; a small fraction of these cause serious medical conditions or death. (The ratio is probably under 1.5%, as only about 1.5% of the genome encodes protein genes)

==Heinemann, ISBN 0-7506-4069-3. Wild type refers to the most common phenotype in the natural population, however this may, over a period of time, be replaced by a mutant form, which then becomes the new wildtype. The phenotype can be dominant or recessive. Naturally occurring mutant phenotypes play a role in evolution.

In biology, mutations are changes to the base pair sequence of genetic material (either DNA or RNA). Mutations can be caused by copying errors in the genetic material during cell division and by exposure to ultraviolet or ionizing radiation, chemical mutagens, or viruses, or can occur deliberately under cellular control during processes such as meiosis or hypermutation. In multicellular organisms, mutations can be subdivided into germline mutations, which can be passed on to descendants, and somatic mutations. The somatic mutations cannot be transmitted to descendants in animals. Plants sometimes can transmit somatic mutations to their descendants asexually or sexually (in case when flower buds develop in somatically mutated part of plant).

Mutations create variation in the gene pool, and the less favorable (or deleterious) mutations are removed from the gene pool by natural selection, while more favorable (beneficial or advantageous) ones tend to accumulate, resulting in evolutionary change. For example, a butterfly may develop offspring with a new mutation caused say by ultraviolet light from the sun. In most cases, this mutation is not good, since obviously there was no 'purpose' for such change at the molecular level. However, sometimes a mutation may change, say, the butterfly's color, making it harder for predators to see it; this is an advantage and the chances of this butterfly surviving and producing its own offspring are a little better, and over time the number of butterflies with this mutation may form a large percentage of the species. Neutral mutations are defined as mutations whose effects do not influence the fitness of either the species or the individuals who make up the species. These can accumulate over time due to genetic drift. The overwhelming majority of mutations have no significant effect, since DNA repair is able to mend most changes before they become permanent mutations, and many organisms have mechanisms for eliminating otherwise permanently mutated somatic cells.