In addition, all four PTAs correlated significantly with age (Figure 1B, PTA-LF: p = 0.000016, R2 = 0.1929; PTA4: p < 0.00001, R2 = 0.3182; PTA-HF: p < 0.00001, R2 = 0.8426; PTA-EHF: p < 0.00001, R2 = 0.8185). This evidence concerns the gene EHF and hydrops fetalis.