For instance, GNAO1 (G protein subunit alpha o1), whose loss-of-function (LOF) mutations are associated with epileptic encephalopathy but whose gain-of-function (GOF) and synonymous mutations are associated with patients with movement disorders that may not display epilepsy [49] or SLC7A6OS (solute carrier family 7 member 6 opposite strand), has recently been found in two unrelated progressive myoclonus epilepsy families, but its role in epilepsy is unknown [50]. Here, SLC7A6 is linked to epilepsy.