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Multiple Allelism

Multiple Alleles

As each gene may exist in alternative forms known as alleles, which code for different versions of a particular inherited character. 
  • A part from that some genes may exist in three or more allelic which may be called as multiple alleles. 
  • It is important to note that while multiple alleles occur and are maintained within a population, any individual possesses only two such alleles (at equivalent loci on homologous chromosomes).

Characteristics of Multiple allelism

  • A single gene has more than 2 alleles.
  • Only 1 allele of a particular gene occupied by a gamete or a chromosome.
  • Various alleles of the same gene express different alternative of same trait.
  • Multiple alleles in a homologous chromosome occupy the similar locus.
Examples of Multiple Allelism
  1. ABO Blood group in Humans.
  2. Skin Colour.
  3. Eye colour in Drosophila.
  4. Coat colour in Rabbit.

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