One exception is megalencephalic leukoencephalopathy with subcortical cysts, a leukodystrophy caused by MLC1 or GlialCAM mutations encoding for components of the dystrophin associated glycoprotein complex, coupled to AQP4 water channels and Kir4.1 K + channels [104, 105]. The gene discussed is ART4; the disease is leukodystrophy.