Dnmt3l-/+ (maternal methylation-deficient) vs normal 8.5dpc embryos

During oogenesis, DNA methyltransferase 3-like (Dnmt3l) is required for the establishment of the maternal germline DNA methylation imprints that in the offspring, govern the parent-of-origin-specific expression of most known imprinted genes (Science 2001, 294:2536-9). Dnmt3l-deficient dams were crossed with wildtype sires to obtain Dnmt3l-/+ embryos that lack maternal methylation imprints. Gene expression was measured in Dnmt3l-/+ and wildtype embryos and is expected to differ for imprinted genes that are under the control of a maternal methylation mark.

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