Genomic Imprinting

Genomic Imprinting is an example of epigenetic inheritance in eutherian mammals in which the gene expression depends on the parental origin of the allele, i.e. a particular gene will be expressed only from one specific parental allele, thereby leading to monoallelic expression.


The parental specific expression of genes is due to the epigenetic modification that differentially marks the parental alleles during gametogenesis. Most of the genes involved in embryo development are imprinted. (IGF2, H19, etc).

Epigenetic changes are alterations in gene expression without affecting the primary DNA sequence thereby modulating gene function. The epigenetic modifications involve DNA methylation, chromatin remodeling through histone modifications, etc. The best characterized epigenetic mark for gene imprinting is DNA methylation at specific regions known as differentially methylated regions (DMR).