ABSTRACT
We present prenatal diagnosis of mucopolysaccharidosis type II (MPS II) (Hunter syndrome) and demonstrate marked mucopolysaccharide deposition in multiple vital organs in a 22-gestational-week affected fetus. Level II ultrasound showed cardiomegaly and hepatomegaly. Histological examinations of the fetal vital organs manifested marked mucopolysaccharide deposition. We suggest that any therapeutic approach and counseling for prenatally diagnosed MPS II should consider the early signs of in utero marked mucopolysaccharide storage.
Subject(s)
Genetic Counseling , Mucopolysaccharidosis II/diagnosis , Prenatal Diagnosis , Aborted Fetus/pathology , Abortion, Induced , DNA Mutational Analysis , Female , Glycoproteins/genetics , Glycosaminoglycans/analysis , Humans , Male , Mucopolysaccharidosis II/diagnostic imaging , Mucopolysaccharidosis II/embryology , Mucopolysaccharidosis II/pathology , Mutation, Missense , Pregnancy , Pregnancy Trimester, Second , Ultrasonography, PrenatalABSTRACT
We report the occurrence of Hunter disease (mucopolysaccharidosis type II) in a karyotypically normal girl who was one of identical twins. Molecular studies showed nonrandom X-inactivation in both her fibroblasts and lymphocytes, while her normal twin showed equal usage of both X chromosomes. In view of previous reports of 7 pairs of identical female twins in which one had Duchenne muscular dystrophy, it seems that twinning may be strongly associated with nonrandom X-inactivation, and is not specific to the properties of the disease causing gene.
Subject(s)
Diseases in Twins/genetics , Dosage Compensation, Genetic , Mucopolysaccharidosis II , Mucopolysaccharidosis II/genetics , Twins, Monozygotic , DNA Probes , Female , Fibroblasts/ultrastructure , Glycosaminoglycans/metabolism , Heterozygote , Humans , Iduronate Sulfatase/genetics , Infant, Newborn , Leukocytes/ultrastructure , Models, Genetic , Mucopolysaccharidosis II/embryology , PedigreeABSTRACT
A prenatal diagnosis of Mucopolysaccharidosis II (M. Hunter) was made early in a pregnancy at risk in a family with one affected child. An affected fetus was diagnosed on the basis of an abnormal incorporation and degradation of 35SO4 in 35SO4-labeled mucopolysaccharides in cultured amniotic cells. Dermatan sulfate and heparin sulfate concentrations in the supernatant of the amniotic fluid were high. In the aborted fetus, the diagnosis could be confirmed by 35SO4 incorporation studies in the cultured fibroblasts and in cultured brain cells as well as by the deficiency of the specific enzyme activity (iduronide sulfate sulfatase) in the organs of the fetus. beta-Galactosidase was in the low normal range in liver and spleen but significantly reduced in brain. Under electron microscopy, the mesenchymal cells of liver and spleen showed lysosomal storage of material, presumably mucopolysaccharides, in excess of normal. In the neurons of the spinal ganglia and spinal cord, "Zebra bodies" in statu nascendi were observed.
