Prenatal diagnosis of congenital alveolar proteinosis (surfactant protein B deficiency)

We report on the DNA‐based prenatal diagnosis of congenital pulmonary alveolar proteinosis in a family in which alveolar proteinosis was associated with surfactant protein B (SP‐B) deficiency. The parents had lost an eight‐week‐old female child due to this fatal disorder. The affected child was homozygous and both parents were heterozygous for a frame‐shift mutation in codon 121 of the surfactant protein B gene (SFTP3‐gene). Chorionic villus sampling (CVS) was performed in two subsequent pregnancies. DNA analysis revealed homozygosity for the codon 121 mutation in the first fetus, and the pregnancy was terminated. Homozygosity for the parental wild‐type alleles was detected in the following prenatal diagnosis, and a healthy child has been born.