Rare Variant of GM2 Gangliosidosis through Activator-Protein Deficiency

Florian Brackmann; Christiane Kehrer; Wibke Kustermann; Judith Böhringer; Ingeborg Krägeloh-Mann; Regina Trollmann

doi:10.1055/s-0037-1598646

Neuropediatrics, Table of Contents

Neuropediatrics 2017; 48(02): 127-130
DOI: 10.1055/s-0037-1598646

Short Communication

Georg Thieme Verlag KG Stuttgart · New York

Rare Variant of GM2 Gangliosidosis through Activator-Protein Deficiency

Florian Brackmann

¹Division of Neuropediatrics, Department of Pediatrics, University Hospital Erlangen, Erlangen, Germany

,

Christiane Kehrer

²Department of Pediatric Neurology, University Children's Hospital, Tübingen, Germany

,

Wibke Kustermann

¹Division of Neuropediatrics, Department of Pediatrics, University Hospital Erlangen, Erlangen, Germany

,

Judith Böhringer

²Department of Pediatric Neurology, University Children's Hospital, Tübingen, Germany

,

Ingeborg Krägeloh-Mann

²Department of Pediatric Neurology, University Children's Hospital, Tübingen, Germany

,

Regina Trollmann

¹Division of Neuropediatrics, Department of Pediatrics, University Hospital Erlangen, Erlangen, Germany

› Author Affiliations

Abstract

GM2 gangliosidosis, AB variant, is a very rare form of GM2 gangliosidosis due to a deficiency of GM2 activator protein. We report on two patients with typical clinical features suggestive of GM2 gangliosidosis, but normal results for hexosaminidase A and hexosaminidase B as well as their corresponding genes. Genetic analysis of the gene encoding the activator protein, the GM2A gene, elucidated the cause of the disease, adding a novel mutation to the spectrum of GM2 AB variant. This report points out that in typical clinical constellations with normal enzyme results, genetic diagnostic for activator protein defects should be performed.

Keywords

sphingolipidoses - GM2 gangliosidosis - activator protein - Tay–Sachs' disease

Full Text

References

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