Epigenetic phenomena are being increasingly recognized to play key roles in normal mammalian development and disease. This is exemplified by the process of genomic imprinting whereby despite identical DNA sequence, the two parental chromosomes are not equivalent and show either maternal- or paternal-specific expression at a subset of genes in the genome. These patterns are set up by differentia...

Although methylation has been recognized as an important component in a number of developmental processes in mammals, in zebrafish almost nothing is known about this epigenetic modification. This is despite the fact that the zebrafish is becoming increasingly popular as a developmental model system. The little work that has been done on methylation and development in fish concerns genomic impri...

The study of variegating position effects in Drosophila provides a model system to explore the mechanism and material basis for the construction and developmental control of heterochromatin domains and the imprinted genomic structures that they may create. The results of our experiments in this regard have implications for a diverse assortment of long-range chromosome phenomena related to gene ...

Human offspring are weaned earlier than the offspring of other great apes but take longer to reach nutritional independence. An analysis of human disorders of imprinted genes suggests genes of paternal origin, expressed in infants, have been selected to favor more intense suckling than genes of maternal origin. The same analysis suggests that genes of maternal origin may favor slower childhood ...

of the germ lines. Previous data have suggested that in nonmalignant tissues an imprint is constant throughout life and is not susceptible to modification, except during gametogenesis. The present study examines allelic expression of the IGF2 gene in human liver during postnatal development. The data show that the IGF2 gene is imprinted (i.e., monoallelically expressed) in liver at the age of 6...

Genomic imprinting often results in parent-of-origin specific differential expression of maternally and paternally inherited alleles. In plants, the triploid endosperm is where gene imprinting occurs most often, but aside from studies on Arabidopsis, little is known about gene imprinting in dicotyledons. In this study, we inspected genomic imprinting in castor bean (Ricinus communis) endosperm,...