uniparental disomy

genetics

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July 16, 2026

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Uniparental disomy (UPD) is a genetic phenomenon where an individual inherits both copies of a chromosome from a single parent, instead of the usual one from each parent. This can lead to genetic disorders if key genes on that chromosome are imprinted. Genetic imprinting means genes are expressed differently depending on whether they are inherited from the mother or father.12

For example, if a gene is maternally imprinted, it's normally only expressed from

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genomic imprinting
Imprinting and fetal development
… (or Russell-Silver syndrome), a maternal uniparental disomy (both copies of a chromosome or partial chromosome are inherited from one parent), growth restriction is present. Similar effects are found in other cases of disordered imprinting. Preeclampsia, for example, in which disordered imprinting has been implicated, also demonstrates growth restriction in utero.…
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… (or Russell-Silver syndrome), a maternal uniparental disomy (both copies of a chromosome or partial chromosome are inherited from one parent), growth restriction is present. Similar effects are found in other cases of disordered imprinting. Preeclampsia, for example, in which disordered imprinting has been implicated, also demonstrates growth restriction in utero.…
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human genetic disease
Imprinted gene mutations
…now known to result from uniparental disomy, a phenomenon whereby a child is conceived who carries the normal complement of chromosomes but who has inherited both copies of a given chromosome from the same parent, rather than one from each parent, as is the normal fashion. If any key genes…
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…now known to result from uniparental disomy, a phenomenon whereby a child is conceived who carries the normal complement of chromosomes but who has inherited both copies of a given chromosome from the same parent, rather than one from each parent, as is the normal fashion. If any key genes…
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