There are nephrotic manifestations of human COL4A1 mutations of the Hereditary Angiopathy, Nephropathy, Aneurysms, and Muscle Cramps (HANAC) syndrome [21] and recent research revealed glomerular hyperpermeability and adult onset glomerulocystic kidney disease in association with COL4A1 mutations [4]. Here, COL4A1 is linked to muscle cramp.