Some human embryonic stem cell lines have shown genomic instabilities over long-term culture. To study the controversial origin of the SCNT-hES-1 line, which was derived from autologous somatic cell nuclear transfer (SCNT), we compared the expression and methylation patterns of imprinted genes in the SCNT-hES-1 cells with the donor's somatic cells by semi-quantitative RT-PCR, real-time PCR and ...

Genomic imprinting in mammals is an epigenetic process that results in differential expression of the two parental alleles. The tightly linked murine H19 and Igf2 genes are reciprocally imprinted: H19 is expressed from the maternal chromosome while Igf2 is expressed from the paternal chromosome. A single regulatory region in the 5' flank of the H19 gene has been implicated in silencing both gen...

Insight into how the mammalian genome is structured in vivo is key to understanding transcriptional regulation. This is especially true in complex domains in which genes are coordinately regulated by long-range interactions between cis-regulatory elements. The regulation of the H19/Igf2 imprinted region depends on the presence of several cis-acting sequences, including a methylation-sensitive i...

Epigenetic variation may significantly contribute to the risk of common disease. Currently, little is known about the extent and causes of epigenetic variation. Here, we investigated the contribution of heritable influences and the combined effect of environmental and stochastic factors to variation in DNA methylation of the IGF2/H19 locus. Moreover, we tested whether this locus was subject to ...

Both the early environment and genetic variation may affect DNA methylation, which is one of the major molecular marks of the epigenome. The combined effect of these factors on a well-defined locus has not been studied to date. We evaluated the association of periconceptional exposure to the Dutch Famine of 1944-45, as an example of an early environmental exposure, and single nucleotide polymor...

imprinted expression of most, though not all, known imprinted genes (reviewed in Tilghman, 1999). Differentially methylated regions have also been consistently Edinburgh EH4 2XU correlated with imprinted loci. On mouse chromosome United Kingdom 7, the region upstream of H19 (the imprinting control region—ICR) is methylated only on the paternally derived allele. It is now clear that the ICR orch...