The report of the remarkable therapeutic action of glycine1 in progressive muscular dystrophy by Thomas, Milhorat and Techner2 has been followed by wide-spread trial of this substance in the dystrophies and in other diseases primarily involving the muscles. Beneficial effects in muscular dystrophy have been substantiated by Kostakow and Slauck,3 Chanutin, Butt and Royster,4 and Beard and Tripoli.5 Boothby6 and Remen7 have shown that glycine is of value also in the treatment of myasthenia gravis. It would appear, however, that the treatment of muscular dystrophy has not been successful in many instances and that certain patients suffering from this disease do not respond to glycine therapy. This is evident from the reports of Boothby,6 Milhorat,8 and Brand and Harris.9 Aside from the suggestion of the latter that glycine may be effective only in certain forms of muscular dystrophy, there is