Molecular Genetics of Genomic Imprinting

Abstract

Genomic imprinting is a developmental mechanism in placental mammals leading to the repression or expression of genes, depending on whether they are inherited from the mother or the father. The imprinted expression of genes is regulated by various epigenetic alterations, including DNA methylation and covalent modifications on histones. A large number of imprinted genes have been identified. Mostly organized in gene clusters in the genome, imprinted genes play important roles in embryonic and extraembryonic development, and in behavior. In humans, genetic and epigenetic alterations at imprinted gene clusters are involved in different disease syndromes, and in cancer.