Neural Tube Defects Cannot Be Diagnosed Prenatally by Electrophoresis of Amniotic Fluid Transferrin Isoforms

Prenatal diagnosis of neural tube defects (NTDs) is based on ultrasonography; but uncertainty exists in a few cases, and biochemical analysis of amniotic fluid (AF) is required. Electrophoresis of AF acetylcholinesterase is a specific and sensitive method for diagnosis of myelomeningocele (1)(2). Although false-positive results are rare, another biochemical technique would be of great value. Adult and infant cerebrospinal fluid (CSF) is characterized by a specific marker, asialotransferrin or β2-transferrin, because it migrates more slowly in electrophoresis than β1-tetrasialotransferrin, the main isoform in all biological fluids (3). The specific behavior of β2-transferrin is used for the detection of CSF leakage from the subarachnoid space into the nasal or aural cavity (4)(5). Assuming that CSF would leak from a myelomeningocele-affected fetus into the AF, we screened AF …