Dictionary > Aneuploidy

Aneuploidy

Definition
noun
(genetics) The chromosomal variation due to a loss or a gain of one or more chromosomes resulting in the deviation from the normal or the usual number of chromosomes for that species
Supplement
Improper cell divisions may lead to chromosomal variations. One possible outcome is aneuploidy. Another common chromosomal variation is euploidy. Euploidy is a chromosomal variation involving the entire set of chromosomes in a cell or an organism. In aneuploidy, not all of the chromosomes are involved. It may be due to one or more chromosomes but not the entire set. The chromosomal variation may be caused by a lack of or a gain of a copy from the usual chromosomal number. The different conditions of aneuploidy are nullisomy (2N-2), monosomy (2N-1), trisomy (2N+1), and tetrasomy (2N+2). The suffix –somy is used rather than –ploidy. This is essential so that confusion may be avoided between the different types of aneuploidy and the types of euploidy (e.g. monoploidy, diploidy, triploidy, tetraploidy, etc). Furthermore, karyotyping of an aneuploidy (i.e. a cell or an organism displaying aneuploidy) would not be a multiple of the haploid or basic chromosomal number as seen in euploidy.
As an example, the human somatic cell usually has a chromosomal number of 46. In aneuploidy, the chromosomal number may become 45 or 47. One possible cause of the gain or loss of chromosome is when a chromosome does not separate properly (nondisjunction) between the two cells during cell division.
See also:

Related form(s):

  • aneuploidy (adjective, of, relating to, or characterized by, aneuploidy)


    You will also like...

    DNA - schematic
    Genetic Mutations

    This tutorial looks at the mutation at the gene level and the harm it may bring. Learn about single nucleotide polymorph..

    Lake Wakatipu, New Zealand
    New Zealand’s Unique Geographical History

    Explore why New Zealand has such unique flora and fauna, and learn why long periods of geographical isolation. This less..

    Gibberellins and Gibberellic Acid
    Gibberellins and Gibberellic Acid

    This tutorial describes the role of gibberellin family in plants. Find out the effects of gibberellin on plant growth an..

    Muscle
    Muscle

    Muscle cells are specialized to generate force and movement. Learn about the different types of muscle tissues in this t..

    takahē
    Takahē (Porphyrio hochstetteri)

    Meet the colorful takahē, an extremely rare flightless bird. Find out more about its unique features and why they matte..

    Still freshwater and plants
    Still Freshwater & Plants

    Plants in lentic habitats have features not found in terrestrial plants. They acquired these features as they adapt to t..