G404(P) Detection rate ofslc2a1gene variants causing glucose transporter 1 deffiency syndrome in patients with childhood onset epilepsy

Abstract

Background SLC2A1 gene is the gene gives instruction for production of a protein called Glucose transporter 1( GLUT1). Alterations (variants) on this gene affect the production of enough amounts and reduce function of GLUT1 protein. This protein is responsible of transporting sugar particles (glucose) from the blood stream across the blood brain barrier to the brain. Glucose is the main source of fuel for the brain without which the brain will not develop and function properly, this manifest as a neurological disorder known as GLUT1 deficiency syndrome. GLUT1 deficiency syndrome can present with different features like fits (epilepsy), developmental delay, learning disabilities and some do present with movement disorder. These features are not specific to GLUT1 deficiency syndrome and overlap and shared with other epileptic disorders. Ketogenic diet is known to be effective in these patients. Result In this study we looked at the result of patients who were clinically suspected to have GLUT1 deficiency syndrome. The SLC2A1 gene was analysed for these patients. Out of 1038 patients 38 were found to have alteration in this gene, 29 (2.8%) of which were confirmed to be causing GLUT1 deficiency. Most of these gene alterations were new and not inherited from either parent. Some had inherited the gene alteration from an affected parent with mild symptoms. We looked at the type of these gene variants and their predicted effect on the protein. Conclusion We concluded that the detection rate is relatively small, as the clinical symptoms greatly overlap with other neurological epileptic disorders. To maximise the testing potential, patients might benefit from multi genes panel analysis like the recently developed and promising next generation sequencing method.