Summary
The mean activities of N-acetyl-β-D-glucosaminidase, β-D-glucuronidase, arylsulphatase A and β-D-galactosidase in the serum of 10 proved heterozygotes for the mutant gene causing I-cell disease (ICD) are significantly different from those in age-matched control sera. Overlapping of individual results in both groups renders assay of serum acid hydrolases an impractical method of reliable detection of the ICD heterozygous genotype.
That the mutant gene is also partially expressed in heterozygote serum, may be useful in assessing existing hypoteses on the nature of its primary metabolic defect.
Zusammenfassung
Es zeigte sich, daß die durchschnittliche Aktivität der N-Acetyl-β-D-Glucosaminidase, der β-D-Glucuronidase, der Arylsulfatase A und der β-D-Galaktosidase im Serum von 10 Patienten, die gesichert heterozygot für das Gen waren, das die Inclusion-Cell Disease (ICD) verursacht, sich signifikant unterscheidet von der Aktivität in Seren einer altersentsprechenden Kontrollgruppe. Da sich die beiden Gruppen hinsichtlich ihrer Aktivitäten der sauren Serumhydrolasen überschneiden, erscheint ein Bestimmen dieses Enzyms für eine wohlfundierte Untersuchung auf einen heterozygoten Genotypus bezüglich der ICD ungeeignet.
Die Tatsache, da\ sich im Serum eines Heterozygoten das mutierte Allel ebenfalls teilweise manifestiert, mag als eine Hilfe gelten für die Entscheidung, welche von den z. Z. bestehenden Hypothesen bezüglich der Ursache dieses primär metabolischen Defektes die richtige ist.
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Leroy, J.G., Van Elsen, A.F. I-Cell disease (mucolipidosis type II) serum hydrolases in obligate heterozygotes. Humangenetik 20, 119–123 (1973). https://doi.org/10.1007/BF00284846
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DOI: https://doi.org/10.1007/BF00284846