Differential expression of the same gene depending on parent of origin is referred to as –

The phenomenon referred to as genomic imprinting leads to pereferential expression of an allele depending on its parental origin - Harrisons Genomic imprinting Human inherits two copies of each gene, i.e. two alleles, from homologous maternal and paternal chromosomes. There is no functional difference between the genes derived from the mother or the father. But, with respect to some genes, there are functional differences between the paternal gene and maternal gene. These differences result from an epigenetic process, called genomic imprinting. In most cases, genomic imprinting selectively inactivates either the maternal or paternal allele. 1. Maternal genomic imprinting Selective inactivation of the maternal allele An example is an Angelman syndrome 2. Paternal genomic imprinting Selective inactivation of paternal allele. An example is Prader-Willi syndrome.