Amniotic fluid alpha-fetoprotein microheterogeneity in the prenatal diagnosis of congenital disorders of glycosylation type Ia
Abstract
Congenital disorders of glycosylation (CDG) are a group of clinically and biochemically diverse defects. The current screening methods (based on analysis of transferrin),which are used postnatally for the most frequent types, are however not suitable for prenatal diagnosis.
The aim of the study was to investigate whether alterations in the microheterogeneity of alpha-fetoprotein in amniotic fluid would provide more reliable results. Isoelectric focusing with direct immunofixation and silver staining was used for analyses.
A difference in the relative proportion of individual alpha-fetoprotein bands (particularly increase of band II density) was found in a case where CDG has been diagnosed postnatally, and in two other samples from pregnancies which resulted in termination, without further examination. Verification of our results in another laboratory with the exclusion of several potentially pertinent variables is advisable.