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Definition of polysomy

by Alivia Nyhan
Published: Last Updated on

Polysomy is a chromosomal aberration disease caused by the presence of extra chromosomes on one pair of somatic or sex chromosomes. In medicine, polysomy is understood as the quality of a fetus with more than two bodies. This word comes from the Greek: “poly” means a lot or many and “soma” means body. This reduplication of one or more chromosomes occurs as a result of chromosome non-separation during meiotic division in gamete maturation. At FastlyHealwe explain in more detail the definition of polysomy .

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Presence of at least one triplicate chromosome in otherwise normal diploid somatic cells, as a consequence of chromosomal non-disjunction during meiotic division in gamete maturation. The chromosome can be duplicated three times (trisomy), four times (tetrasomy), or more times.

More about polysomy

In medicine, polysomy is the quality of a fetus with more than two bodies.

In the field of genetics, polysomy is the reduplication of one or more chromosomes above the normal diploid number. There are trisomies when doubling three times, tetrasomies when doubling four times, etc. The explanation for this phenomenon is the non-separation of chromosomes during meiotic division in the maturation of gametes. These genetic abnormalities are common in different syndromes, and can sometimes be fatal.

The best known trisomy is that of chromosome 21, which causes Down syndrome. People who live with this condition have some physical and mental features in common, such as a high and flattened forehead, puffy eyes, short stature, muscular hypotonia and other malformations. Of all patients with Down syndrome, 95% have forty-seven chromosomes in all of their cells. The remaining 5% have alterations in certain cells, and are known as patients with mosaicism.

This article is merely informative, at FastlyHeal .com we do not have the power to prescribe medical treatments or make any type of diagnosis. We invite you to see a doctor in the case of presenting any type of condition or discomfort.

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