Overview
- Glycogen Storage Diseases (GSD) are a group of inherited disorders that result from errors of glycogen metabolism caused by mutations in genes that code for enzymes involved in glycogen synthesis and degradation. There are five types of Glycogen Storage Diseases according to their individual enzyme deficiency, type 1 or von Gierke disease being the most common type. The age of onset of symptoms may range from the first months of life to later decades in life. Symptoms arise from abnormal glycogen metabolism and accumulation of glycogen within cells of certain tissues (i.e., liver and skeletal muscles).
- The Igenomix Glycogen Storage Diseases Precision Panel can be used to make an accurate and directed diagnosis as well as a differential diagnosis of hypoglycemia ultimately leading to a better management and prognosis of the disease. It provides a comprehensive analysis of the genes involved in this disease using next-generation sequencing (NGS) to fully understand the spectrum of relevant genes involved.
Indication
- The Igenomix Glycogen Storage Diseases Precision Panel is indicated for those patients with a clinical suspicion or diagnosis with or without the following manifestations:
- Hypoglycemia
- Hepatomegaly
- Poor growth
- Increased uric acid, lactic acid and triglycerides
- Cardiomegaly
- Muscle hypotonia
- Delayed gross motor development
- Respiratory difficulty
- Muscle cramp and fatigue
Clinical Utility
The clinical utility of this panel is:
- The genetic and molecular confirmation for an accurate clinical diagnosis of a symptomatic patient.
- Early initiation of treatment with a multidisciplinary team in the form of nutritional management with frequent oral glucose consumption and enzyme replacement therapy.
- Risk assessment and genetic counselling of asymptomatic family members according to the mode of inheritance.
- Improvement of delineation of genotype-phenotype correlation.
References
Ellingwood, S. S., & Cheng, A. (2018). Biochemical and clinical aspects of glycogen storage diseases. The Journal of endocrinology, 238(3), R131–R141. https://doi.org/10.1530/JOE-18-0120
Hicks, J., Wartchow, E., & Mierau, G. (2011). Glycogen storage diseases: a brief review and update on clinical features, genetic abnormalities, pathologic features, and treatment. Ultrastructural pathology, 35(5), 183–196. https://doi.org/10.3109/01913123.2011.601404
Kishnani, P. S., Sun, B., & Koeberl, D. D. (2019). Gene therapy for glycogen storage diseases. Human molecular genetics, 28(R1), R31–R41. https://doi.org/10.1093/hmg/ddz133
Ross, K. M., Ferrecchia, I. A., Dahlberg, K. R., Dambska, M., Ryan, P. T., & Weinstein, D. A. (2020). Dietary Management of the Glycogen Storage Diseases: Evolution of Treatment and Ongoing Controversies. Advances in nutrition (Bethesda, Md.), 11(2), 439–446. https://doi.org/10.1093/advances/nmz092
Kishnani, P. S., Goldstein, J., Austin, S. L., Arn, P., Bachrach, B., Bali, D. S., Chung, W. K., El-Gharbawy, A., Brown, L. M., Kahler, S., Pendyal, S., Ross, K. M., Tsilianidis, L., Weinstein, D. A., Watson, M. S., & ACMG Work Group on Diagnosis and Management of Glycogen Storage Diseases Type VI and IX (2019). Diagnosis and management of glycogen storage diseases type VI and IX: a clinical practice resource of the American College of Medical Genetics and Genomics (ACMG). Genetics in medicine : official journal of the American College of Medical Genetics, 21(4), 772–789. https://doi.org/10.1038/s41436-018-0364-2
Derks, T., Oosterveer, M. H., & De Souza, C. F. (2018). Next-generation glycogen storage diseases. Journal of inherited metabolic disease, 41(6), 911–912. https://doi.org/10.1007/s10545-018-00250-0