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. Here, PHKG2 is linked to disorder of glycogen metabolism.