ACTA1 and myotonic dystrophy type 1: To date, ASOs are the most promising therapeutic agents for DM1.6, 7, 8,11,37 We treated 14-month-old HSALR mice for 3 months with saline or a therapeutic ASO that targets the ACTA1-CUGexp transcripts for cleavage via the RNase H pathway and reverses the molecular phenotype in young HSALR mice.6