The MYH1 genetic mutation can strike horses in two ways, causing extreme damage to the horse's muscles -- including IMM. Though the mutation is permanent, experts say owners of horses who have it can take steps to minimize risk and quickly treat any disease. • Photo by Molly Montag.

Living With MYH1

The recently discovered MYH1 genetic mutation can cause debilitating illness, but experts say horse owners can take steps to lessen the chances of triggering serious muscular damage.