miRagen Therapeutics, Inc. announced the appointment of Jonathan Violin, Ph.D., M.B.A. as President and member of the Board of Directors.   Dr. Violin, who previously served as Viridian’s President and Chief Operating Officer (COO), succeeds Lee Rauch as CEO and member of the Board of Directors.   Ms. Rauch will remain as strategic advisor for the Company. In addition, Viridian appointed internationally recognized neuro-ophthalmologist, Barrett Katz M.D., M.B.A., as Chief Medical Officer (CMO).   Dr. Katz comes to Viridian from BridgeBio Pharma, Inc. where he developed therapeutics to treat orphan eye diseases.