A method for the determination of amniotic-fluid glycosaminoglycans and its application to the prenatal diagnosis of Hurler and Sanfilippo diseases.

A new and simple micromethod for the determination of individual glycosaminoglycan components in small volumes of amniotic fluid is described. Two-dimensional electrophoresis demonstrated an abnormal content of dermatan and heparan sulphates in amniotic fluid from pregnancies affected by Hurler disease (two at 14 weeks' and one at 16 weeks' gestation), and of heparan sulphate in amniotic fluid from pregnancies affected by Sanfilippo disease (16 and 25 weeks' gestation). Excellent discrimination between normal and affected pregnancies was provided by an estimation of the dermatan sulphate:chondroitin sulphate ratio (Hurler disease) and the heparan sulphate: chondroitin sulphate ratio (Sanfilippo disease); the use of external glycosaminoglycan standards was then unnecessary.