GENOMIC IMPRINTING AS A GENERAL MECHANISM OF GENE-FUNCTION DURING DEVELOPMENT

The term genomic imprinting is used to designate the phenomenon of fun ctional nonequivalence of alleles whose activities depend on their par ental origin. A functional hemizygosity of the gene is characteristic for genomic imprinting. However, activities of alleles also depend on their parental origin in some cases of diallelic gene expression. Thes e cases are described in the literature as possible examples of imprin ting. In this paper, different manifestations of genomic imprinting ar e analyzed, and a hypothesis is suggested about the murine genome as a set of genes with different-expression of homologous alleles, whose a ctivities depend on their parental origin.