Common features among this group included nuchal edema and pleural effusions that were similar to phenotypes observed in recently described PIEZO1 cases.39 Homozygous or compound heterozygous variants in PIEZO1 are associated with GLAs and marked fetal hydrops, while heterozygous variants are associated with DHS with or without perinatal edema.19,30,45–49 We identified a novel homozygous PIEZO1 missense VOUS in a fetal case of marked hydrops, where neonatal demise occurred on day of life one due to respiratory distress secondary to chylothorax. The gene discussed is PIEZO1; the disease is Chylothorax.