CDKN1A and hydrops fetalis: The findings suggest that heat shock protein family A member 1B (HSPA1B), cyclin-dependent kinase inhibitor 1A (CDKN1A) may serve as potential genes, and the overall causal effects of cis-eQTL of all genes on HF were summarized (Figure 3; Additional file 1: Supplementary Tables S5, S8, S9).