Glycogen storage disease type 0: a novel deleterious mutation

Introduction: Glycogen storage disease type 0, liver (liver GSD 0), a form of glycogen storage disease (GSD), which is not the predominant form of autosomal recessive glycogen storage disease (GSD) is a rare form of abnormality of glycogen metabolism characterized by glycosuria, irritability, ketonuria, ketosis and ketotic hypoglycemia. Other symptoms typically appear in infancy or in early childhood and may include drowsiness, sweating, lack of attention, fasting hypoglycemia associated with hyperketonemia, seizures, and other findings. It is caused by a deficiency of the enzyme glycogen synthetase in the liver, due to mutations in the GYS2 gene. The GYS2 gene provides instructions for making an enzyme called liver glycogen synthase. Liver glycogen synthase is produced solely in liver cells, where it helps form the complex sugar glycogen by linking together molecules of the simple sugar glucose. Up to now, it is estimated 20 mutations in the GYS2 gene have been found to cause a form of GSD 0 that affects the liver.Materials & Methods: The patient was a 6-month old infant with consanguineous parents and severe hypoglycemia symptoms including arrhythmia and lethargy, lip and tongue swelling, severe myopathy, and fever. Since parents were consanguineous, we assessed them with whole exome sequencing (WES) and their relatives with sanger method.Results: The current research represents novel homozygous mutation, NM_021957:exon1: c.C7T:p.R3X, that is leads to Glycogen storage disease 0, (OMIM;240600). Our bioinformatic analysis showed that these variation is pathogenic and result in truncated protein. Co-segregation analysis revealed the parents were heterozygous for the variant.Conclusion & discussion: These findings state vital role of GSY2 in liver cells and for understanding the disease suggest further studies with special focus on GSY2 role in regulating the processes

کلیدواژه ها:

GSY2 ، Glycogen storage disease 0 ، WES