No single cause of OS has been identified. In most cases, there is severe atrophy of both hemispheres of the brain. Less often, the root of the disorder is an underlying metabolic syndrome. Although it was initially published that no genetic connection had been established,  several genes have since associated with Ohtahara syndrome. It can be associated with mutations in ARX ,   CDKL5 ,  SLC25A22 ,  STXBP1 ,  SPTAN1 ,  KCNQ2 ,  ARHGEF9 ,  PCDH19 ,  PNKP ,  SCN2A ,  PLCB1 ,  SCN8A ,  and likely others.