mosaicism

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mosaicism

genetic disorder

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June 23, 2026

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Mosaicism is a condition where an individual has cells with different genetic makeups. This means that within the same person, there can be a mix of cells that are genetically distinct from each other.1

The term "mosaic inheritance" can refer to two concepts. The first is a supposed inheritance pattern where both parental traits are present, but only one is expressed at a time, similar to how colors appear in variegated flowers. The second definition of mosaic inheritance aligns with typical Mendelian inheritance, where distinct parental traits are passed down.2

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chromosomal disorder
…occur, a condition known as mosaicism. In either case, abnormalities of development occur because of the unusual genetic signals transmitted by the chromosomes. Some one of these chromosome imbalances occurs in 0.5 percent of all births.
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…occur, a condition known as mosaicism. In either case, abnormalities of development occur because of the unusual genetic signals transmitted by the chromosomes. Some one of these chromosome imbalances occurs in 0.5 percent of all births.
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human genetic disease
Abnormalities of the sex chromosomes
…Turner syndrome are diagnosed as mosaics, meaning that some proportion of their cells are 45,X while the rest are either 46,XX or 46,XY. The degree of clinical severity generally correlates inversely with the degree of mosaicism, so that females with a higher proportion of normal cells will tend to have…
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…Turner syndrome are diagnosed as mosaics, meaning that some proportion of their cells are 45,X while the rest are either 46,XX or 46,XY. The degree of clinical severity generally correlates inversely with the degree of mosaicism, so that females with a higher proportion of normal cells will tend to have…
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hermaphroditism
…have sex chromosomes showing male-female mosaicism (where one individual possesses both the male XY and female XX chromosome pairs). Most often, but not always, the chromosome complement is 46,XX, and in every such individual there also exists evidence of Y chromosomal material on one of the autosomes (any of the…
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…have sex chromosomes showing male-female mosaicism (where one individual possesses both the male XY and female XX chromosome pairs). Most often, but not always, the chromosome complement is 46,XX, and in every such individual there also exists evidence of Y chromosomal material on one of the autosomes (any of the…
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trisomy X
…division early in embryonic development, mosaicism occurs, in which the extra X chromosome is present in only some cells.
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…division early in embryonic development, mosaicism occurs, in which the extra X chromosome is present in only some cells.
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Stanisława Walasiewicz
The Curious Story of Stella Walsh
…a chromosomal disorder known as mosaicism that left her with sexually ambiguous genitalia. Despite the gender confusion caused by the disorder, Walsh had lived her entire life as a woman.
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…a chromosomal disorder known as mosaicism that left her with sexually ambiguous genitalia. Despite the gender confusion caused by the disorder, Walsh had lived her entire life as a woman.
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