What is the Difference Between Uniparental Disomy and Genomic Imprinting?

Uniparental disomy (UPD) and genomic imprinting are both genetic processes that can influence the development of certain genetic conditions. Here are the key differences between them:

Uniparental Disomy (UPD):

UPD occurs when a person receives two copies of a chromosome or part of a chromosome from one parent and no copies from the other parent.
UPD can happen as a random event during the formation of egg or sperm cells or may occur in early embryonic development.
In many cases, UPD likely has no effect on health or development, as most genes are not imprinted.
When UPD involves chromosomes 11 or 15, it can lead to complex situations due to the presence of imprinted regions.

Genomic Imprinting:

Genomic imprinting is a process where certain genes are "branded" with the parent of origin, resulting in the differential expression of normal genes depending on whether they were inherited from the mother or father.
Only a small percentage of all human genes undergo genomic imprinting, with two major clusters identified in humans: one on the short arm of chromosome 11 and another on the long arm of chromosome 15.
Imprinted genes are more vulnerable to the negative effects of mutations, as there is no substitute allele when one copy is expressed.
Diseases can result from deletions or mutations in imprinted genes, as well as from uniparental disomy.

In summary, uniparental disomy is a specific genetic event where an individual inherits two copies of a chromosome from one parent, while genomic imprinting is a process that leads to the differential expression of genes depending on their parental origin. These processes can both contribute to the development of genetic conditions, but they operate through different mechanisms.

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What is the Difference Between Uniparental Disomy and Genomic Imprinting?

Comparative Table: Uniparental Disomy vs Genomic Imprinting

Here is a table comparing the differences between Uniparental Disomy and Genomic Imprinting:

Feature	Uniparental Disomy	Genomic Imprinting
Definition	A condition where an individual inherits two copies of a chromosome or a part of the chromosome from one parent.	A phenomenon where the expression of genes depends on the parent of origin, with only one of the two copies of each gene being active.
Process	Random occurrence taking place during the development of gametes.	Primarily takes place during the initial stages of development of an organism.
Inheritance	Involves only one parent.	Involves both parents.
Gene Expression	The effect of uniparental disomy mainly relies on the inheritance and the expression of the genes.	The expression of genes is strictly related to the parental origin, with one allele being silenced and only one staying active in a diploid genome.
Epigenetic Process	Uniparental disomy can lead to diseases by 'activation' or 'deactivation' of certain genes.	Genomic imprinting is implemented by an epigenetic process, most often initiated by methylation of cytosines in a certain DNA-stretch.
Diagnosis	Both processes can be diagnosed with the help of molecular techniques such as Polymerase chain reaction, etc..	Both processes can be diagnosed with the help of molecular techniques such as Polymerase chain reaction, etc..

Please note that both processes take place in eukaryotes, at a molecular level, and involve genetics and inheritance strategies.

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.