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 ass ociated with surfactant protein B (SP-B) deficiency. The parents had l ost an eight-week-old female child due to this fatal disorder. The aff ected child was homozygous and both parents were heterozygous for a fr ame-shift mutation in codon 121 of the surfactant protein B gene (SFTP 3-gene). Chorionic villus sampling (CVS) was performed in two subseque nt pregnancies. DNA analysis revealed homozygosity for the codon 121 m utation in the first fetus, and the pregnancy was terminated. Homozygo sity for the parental wild-type alleles was detected in the following prenatal diagnosis, and a healthy child has been born. DNA-based prena tal diagnosis of congenital alveolar proteinosis is simple, fast and r eliable, and can be performed much earlier in pregnancy than any other method, e.g. the direct measurement of SP-B in amniotic fluid. In fam ilies with a term infant who dies of unexplained respiratory failure, genetic testing of the parents should be evaluated, since the presence of the codon 121 mutation enables prenatal diagnosis in later pregnan cies. (C) 1998 John Wiley & Sons, Ltd.