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Guilherme Mazui

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What is the Difference Between Monosomy and Trisomy?

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Monosomy and trisomy are two types of chromosomal abnormalities that can lead to birth defects and other health issues. The main differences between them are:

  • Trisomy: In this condition, a person has three copies of a particular chromosome instead of the usual two. Trisomy disorders occur when there is an extra copy of a chromosome, resulting in 47 chromosomes instead of 46. Most trisomies are not compatible with life, and they represent about 35% of spontaneous abortions.
  • Monosomy: In this condition, a person has only one copy of a particular chromosome instead of the usual two. Monosomy occurs when there is a missing copy of a chromosome, reducing the total chromosome number to 45. Monosomy is less common than trisomy.

Both trisomy and monosomy are the result of changes in chromosome division before conception, and they usually occur randomly. While some trisomies can be passed from one generation to the next, they generally occur spontaneously. The risk of having a child with a trisomy condition increases after age 35.

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  • What is the Difference Between Monosomy and Trisomy?
  • Comparative Table: Monosomy vs Trisomy

    • Comparative Table: Monosomy vs Trisomy

    Here is a table summarizing the differences between monosomy and trisomy:

    Feature Monosomy Trisomy
    Description The absence of one copy from the normal pair of chromosomes The presence of three copies of a particular chromosome instead of two
    Chromosome Missing one chromosome or part of a chromosome The affected person has three copies of one chromosome, resulting in 47 chromosomes instead of 46
    Effects Causes deleterious effects in individuals, as missing chromosome changes the overall gene balance Causes deleterious effects in individuals, as the extra chromosome disrupts the balanced genetic makeup
    Examples Turner syndrome (XO) - missing an X chromosome Down syndrome (Trisomy 21) - three copies of chromosome 21
    Risk Factors Risk for monosomy does not increase with maternal age Risk for trisomy does increase with maternal age

    Both monosomy and trisomy are chromosomal abnormalities that occur due to changes in chromosome division before conception. These abnormalities can result in birth defects and other health issues in affected individuals.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.