- GRACILE syndrome, a lethal metabolic disorder with iron overload, is caused by a point mutation in BCS1L. Visapää, I., Fellman, V., Vesa, J., Dasvarma, A., Hutton, J.L., Kumar, V., Payne, G.S., Makarow, M., Van Coster, R., Taylor, R.W., Turnbull, D.M., Suomalainen, A., Peltonen, L. Am. J. Hum. Genet. (2002)