Finally, in humans, a loss of ClC-2 function and dominant mutations of the gene encoding MLC1, a protein that is also highly abundant in the astrocytic endfeet, cause megalencephalic leukoencephalopathy with subcortical cysts, a disease characterized by chronic brain WM oedema in vacuoles predominantly located within myelin sheaths [34, 35]. This evidence concerns the gene MLC1 and leukoencephalopathy, megalencephalic.