New insights into the imprinted MEG8-DMR in 14q32 and clinical and molecular description of novel patients with Temple syndrome

Jasmin Beygo, Alma Küchler, Gabriele Gillessen-Kaesbach, Beate Albrecht, Jonas Eckle, Thomas Eggermann, Alexandra Gellhaus, Deniz Kanber, Ulrike Kordaß, Hermann Josef Lüdecke, Sabine Purmann, Eva Rossier, Johannes Van De Nes, Ilse M. Van Der Werf, Maren Wenzel, Dagmar Wieczorek, Bernhard Horsthemke, Karin Buiting*

*Corresponding author for this work
15 Citations (Scopus)

Abstract

The chromosomal region 14q32 contains several imprinted genes, which are expressed either from the paternal (DLK1 and RTL1) or the maternal (MEG3, RTL1as and MEG8) allele only. Imprinted expression of these genes is regulated by two differentially methylated regions (DMRs), the germline DLK1/MEG3 intergenic (IG)-DMR (MEG3/DLK1:IG-DMR) and the somatic MEG3-DMR (MEG3:TSS-DMR), which are methylated on the paternal and unmethylated on the maternal allele. Disruption of imprinting in the 14q32 region results in two clinically distinct imprinting disorders, Temple syndrome (TS14) and Kagami-Ogata syndrome (KOS14). Another DMR with a yet unknown function is located in intron 2 of MEG8 (MEG8-DMR, MEG8:Int2-DMR). In contrast to the IG-DMR and the MEG3-DMR, this somatic DMR is methylated on the maternal chromosome and unmethylated on the paternal chromosome. We have performed extensive methylation analyses by deep bisulfite sequencing of the IG-DMR, MEG3-DMR and MEG8-DMR in different prenatal tissues including amniotic fluid cells and chorionic villi. In addition, we have studied the methylation pattern of the MEG8-DMR in different postnatal tissues. We show that the MEG8-DMR is hypermethylated in each of 13 non-deletion TS14 patients (seven newly identified and six previously published patients), irrespective of the underlying molecular cause, and is always hypomethylated in the four patients with KOS14, who have different deletions not encompassing the MEG8-DMR itself. The size and the extent of the deletions and the resulting methylation pattern suggest that transcription starting from the MEG3 promoter may be necessary to establish the methylation imprint at the MEG8-DMR.

Original languageEnglish
JournalEuropean Journal of Human Genetics
Volume25
Issue number8
Pages (from-to)935-945
Number of pages11
ISSN1018-4813
DOIs
Publication statusPublished - 01.08.2017

Research Areas and Centers

  • Research Area: Medical Genetics

Fingerprint

Dive into the research topics of 'New insights into the imprinted MEG8-DMR in 14q32 and clinical and molecular description of novel patients with Temple syndrome'. Together they form a unique fingerprint.

Cite this