As genetic variants at the KJCN11 and PHKG2 genes had been previously described in association with Mauriac syndrome [11, 12], an exome gene panel for glycogen storage diseases including AGL, GYS2, PHKA1, PHKA2, PHKB, PHKG2, PYGL and KCNJ11 was analyzed with next generation sequencing technology. The gene discussed is PHKG2; the disease is Glycogen storage disease due to glycogenin deficiency.