a, Strategy of depleting exon 4-7 in the ADD (ATRX-DNMT3-DNMT3L) domain of Dnmt3L (Methods). Inner and outer primers are designed for genotyping. b, Spleen from control and Dnmt3L−/− mice was isolated and western blotting was performed. The asterisk marks possible non-specific band. The arrow marks DNMT3L band. Blot image was cropped (see Supplementary Fig. 13). The experiments were independently performed three times. c, Agarose gel shows the genotyping result of control and Dnmt3L−/− mice by extracting genomic DNA from mouse tail and performing PCR amplification. For mutant mice, the product of inner primer cannot be detected and the outer primer product is truncated. Similar results were obtained from three independent experiments. d, Violin plot showing the levels of DNA methylation in control (n = 2) and Dnmt3L−/− (n = 2) oocytes in FGO. The outer shape indicates all results. The center dot indicates the median average value, and the thick and thin line represent 50% and 95% value ranges, respectively. e, Scatter plot showing gene expression in Dnmt3L+/− and Dnmt3L−/− FGO. Pearson correlation coefficient is shown. Differentially expressed genes are also shown in red (up-regulated) and blue (down-regulated) (2-fold change).