Dictionary > Genomic imprinting

Genomic imprinting

Definition
noun
A phenomenon in which the phenotype of the offspring depends on the source of the chromosome containing the imprinted gene, i.e. whether it is from the female or from the male parent
Supplement
Non-Mendelian inheritance is a type of biological inheritance wherein the patterns of phenotypes do not accord with those as expected in Mendelian laws on inheritance. It includes extranuclear inheritance, gene conversion, infectious heredity, genomic imprinting, mosaicism, and trinucleotide repeat disorders.
Genomic imprinting is a form of non-Mendelian inheritance. It is when the phenotype of the offspring depends on the source of the chromosome containing the imprinted gene whether it is from the female or from the male parent. Epigenetic factors can cause genomic imprinting. An imprinted gene is one in which the DNA is methylated. When methylated, gene expression is suppressed.
Methylated genes are acquired at fertilization. As the zygote develops into a fully grown organism, its somatic cells will bear the same methylated genes. At the time that the organism produces its own gametes, the imprinted genes are un-methylated. Nonetheless, genomic imprints would be re-instituted in its genome. The location of gene methylation would depend on the sex of that organism. The new gene imprints would consequently affect the phenotype of its progeny. The effect would rely upon the sex of that organism transmitting the chromosome containing the methylated gene (i.e. whether it is a female or male parent).
See also:


You will also like...

Hormone Production
Hormone Production

Hormones are chemical messengers produced by specialized glands and they were produced by switching on the genes designe..

Genetics and Evolution
Genetics and Evolution

Humans are diploid creatures. This means that for every chromosome in the body, there is another one to match it. Howeve..

vitamins
A Balanced Vitamin Diet – Vitamins A – K

A balanced diet is essential to a healthy organism. Insufficiency or too much of a particular element or compound, such ..

Peppered moth ("Biston betularia") melanic and light form
Examples of Natural Selection

Darwin's Finches are an example of natural selection in action. They are an excellent example of the way species' gene p..

Biosecurity and Biocontrol
Biosecurity and Biocontrol

This lesson explores the impact of biosecurity threats, and why they need to be identified and managed. Examples to incl..

Lights' Effect on Growth
Lights’ Effect on Growth

This tutorial elaborates on the effect of light on plant growth. It describes how different plants require different amo..