Address of Corresponding Author

Cytogenet Genome Res 2006;113:153-158 (DOI: 10.1159/000090827)

  Abstract.

The mouse H19 and Igf2 genes are oppositely imprinted and share enhancers that reside 3' to the genes. The imprinted expression of these genes is coordinated by a 2-kb regulatory element, the differentially methylated domain (DMD), positioned between the two genes. The methylation status of this region determines the ability of the insulator factor CTCF to bind to its sites in the DMD. Deletions and mutations of the DMD that affect imprinting in the soma have little effect on the methylation pattern of H19 in the germline, suggesting that additional sequences and factors contribute to the earliest stages of imprinting regulation at this locus. Less is known about these initial steps, which include the marking of the parental alleles, the onset of allele-specific expression patterns and maintenance of the imprints in the preimplantation embryo. Here, we will focus on these early steps, summarizing what is known and what questions remain to be addressed.

Copyright © 2006 S. Karger AG, Basel

  Author Contacts

Request reprints from Dr. M.S. Bartolomei
Department of Cell and Developmental Biology
University of Pennsylvania School of Medicine
360 CRB, 415 Curie Blvd., Philadelphia, PA 19104 (USA)
telephone: +1 215-898-9063; fax: +1 215-573-6434
e-mail: bartolom@mail.med.upenn.edu

  Article Information

This work was supported by U.S. Public Health Service grants HD42026 and GM51279 and the Howard Hughes Medical Institute. K.J.R. was supported by National Research Service Award postdoctoral fellowship GM069103.

Manuscript received: 27 August 2005
Accepted in revised form for publication by H. Sasaki,: 12 September 2005.
Number of Print Pages : 6
Number of Figures : 2, Number of Tables : 0, Number of References : 54