uniparental disomy(redirected from Uniparental disomy of 21)
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The inheritance of two copies of a chromosome from one parent and none from the other parent. UPD results in a normal number of inherited chromosomes but with inadequate contribution of genetic material from one of the parents. It may result in the expression of recessive genes, as in Prader-Willi syndrome.
uniparental disomy (UPD)inheritance by offspring of two copies of an homologous chromosome pair from one parent (uniparental) and none from the other parent. Paternal UPD is where both copies are inherited from the father and none from the mother, maternal UPD is where both copies are from the mother and none from the father. There can be two copies of the same chromosome (isodisomy) or one copy of each of the particular parent's chromosomes (heterodisomy). UPD is due to abnormal assortment of chromosomes as a result of NONDISJUNCTION in MEIOSIS and occurs rarely. Health problems associated with UPD include autosomal recessive disorders, such as CYSTIC FIBROSIS, and disorders involving GENOMIC IMPRINTING such as Prader-Willi Syndrome
Chromosome abnormality in which both chromosomes in a pair are inherited from the same parent.
Mentioned in: Prader-Willi Syndrome