genomic imprinting


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genomic imprinting

epigenetic process that leads to inactivation of paternal or maternal allele of certain genes susceptible to epigenetic regulation; accounts, among others, for the Angelman and Prader-Willi syndromes.

ge·nom·ic im·print·ing

(jē-nō'mik im'print-ing)
Epigenetic process that leads to inactivation of paternal or maternal allele of certain genes susceptible to epigenetic regulation; accounts, among others, for the Angelman and Prader-Willi syndromes.

genomic imprinting

The concept, derived from an increasing body of compelling evidence, that the expression of some of the genes depends on whether they have been derived from the father or from the mother. It has been shown, for instance, that chromosomal deletion in chromosomes of parental origin may differ in their effect from the same deletion in the homologous chromosome of maternal origin. Many cancers are associated with loss of a particular chromosome derived from a particular parent—usually the mother. The DNA of some genes is modified during the formation of gametes so as to have altered expression and be activated or inactivated.

genomic imprinting

the process whereby certain genes are modified (principally by METHYLATION) during GAMETOGENESIS, resulting in differential expression of parental alleles depending on whether of maternal or paternal origin. The ‘imprinted’ regions of the DNA are generally less active in transcription. Offspring normally inherit one maternal and one paternal copy of their genes, and generally both copies are active. However, expression of certain genes occurs from only one of the two copies, as a result of imprinting of either the maternal or paternal ALLELE at a particular LOCUS. The phenomenon can occur in a variety of organisms. Only a few human genes are imprinted and they tend to be clustered in the genome. Imprinting may have no effect on health and development, but in some cases can cause medical disorders such as Prader-Willi Syndrome and Angelman Syndrome. See also UNIPARENTAL DISOMY.
References in periodicals archive ?
Some human diseases associated with genomic imprinting
That method sidestepped the problem of genomic imprinting but presents ethical and practical hurdles if this technology were to ever be considered for humans.
Of particular interest in the DOHaD field is genomic imprinting, an epigenetic phenomenon by which parent-of-origin-specific monoallelic gene expression is established during development (Bartolomei and Ferguson-Smith 2011; Das et al.
Daniela Di Tizio wrote the Status of Genomic Imprinting of Human AFSCs and conceived the figures.
PAR supplementation gave promising results also in Prader-Willi syndrome (PWS), a genomic imprinting disorder whose most important feature is severe obesity leading to atherosclerosis and type 2 diabetes mellitus, in which a close relationship with OS has been widely demonstrated [95].
Genomic imprinting: parental influence on the genome.
Assessments of DNA integrity, spindle configuration, aneuploidy and genomic imprinting after cryopreservation
Genomic imprinting refers to differential expression of a locus between the maternally and paternally inherited alleles.
There is only limited evidence of genomic imprinting in oviparous species, such as fish [10].
Family history has been observed in 10% of moyamoya patients (9) and familial moyamoya disease may be autosomal dominant with incomplete penetrance that depends on age and genomic imprinting factors (10).
Two striking epigenetic phenomena in mammalians are X chromosome inactivation (XCI) and genomic imprinting. XCI triggers the transcriptional silencing of most genes in all but one X chromosome in females (1), while genomic imprinting is a process that leads to monoallelic gene expression based on parental origin (2).

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