- Progressive myoclonus epilepsy EPM1 locus maps to a 175-kb interval in distal 21q. Virtaneva, K., Miao, J., Träskelin, A.L., Stone, N., Warrington, J.A., Weissenbach, J., Myers, R.M., Cox, D.R., Sistonen, P., de la Chapelle, A. Am. J. Hum. Genet. (1996)