This method does not directly "cure" the underlying cause of progeria. This method prevents prelamin A from going to the nucleus in the first place so that no prelamin A can build up on the nuclear membrane, but equally, there is no production of normal lamin A in the nucleus. Lamin A does not appear to be necessary for life; mice in which the Lmna gene is knocked out show no embryological symptoms (they develop an Emery–Dreifuss muscular dystrophy-like condition postnatally).[54] This implies that it is the buildup of prelamin A in the wrong place, rather than the loss of the normal function of lamin A, that causes the disease.