NUDT4 and hydrops fetalis: As described in Fig. 4G–H, four of the m7G regulator diagnostic markers (CYFIP1, LARP1, NUDT4, and NUDT16) were significantly downregulated in the heart tissues or plasma samples of HF patients compared with NFDs (p < 0.05), which was consistent with the bioinformatics analysis results, while the differential expression of DCP2 between HF and NFDs was not statistically significant.