In the series collected by Lipitz et al. [15] in 1993, there was a statistically significant difference (p-value: < 0.05) in β2-microglobulin levels between the seven neonates with a prenatal diagnosis of megacystis and a confirmed postnatal diagnosis of PUV who later developed some degree of renal damage and the two neonates with PUV who maintained normal renal function at the last follow-up. The gene discussed is HLA-G; the disease is Megacystis.