Aim: To investigate the DNA-methylation levels in the newly described MEG8 differentially methylated region (DMR) in the imprinted cluster in 14q32 in patients with Temple syndrome.
Patients & methods: We included three patients with Temple syndrome which were studied by Infinium HumanMethylation450 BeadChips, locus-specific bisulfite-pyrosequencing, methylation-specific-MLPA and microsatellite analyses. The tag-CpG of the MEG8-DMR was investigated using the Infinium HumanMethylation450 BeadChip.
Results: In all three patients, the identical pattern of DNA-hypermethylation of the MEG8-DMR was observed along with DNA-hypomethylation of the IG-DMR and MEG3-DMR.
Conclusion: Based on the observed MEG8-DMR DNA-hypermethylation and previously published data, we conclude that DNA-methylation of the MEG3- and MEG8-DMR is functionally dependent on the DNA-methylation pattern of the IG-DMR. The observed combination of epimutations is predicted to be associated with bi-allelic MEG3 and MEG8 expression in individuals with Temple syndrome.
Keywords: DNA methylation; IG-DMR; MEG3; MEG3-DMR; MEG8; MEG8-DMR; Temple syndrome; imprinting.