Muscular dystrophy causes the muscles in the body to become very weak.
The muscles break down and are replaced with fatty deposits over time. It occurs in one out of 3,500 live male births. Muscular dystrophy rarely affects girls, but when it does, the condition is normally not as severe. Our genes determine our traits, such as eye color and blood type. Genes are contained in the cells of our bodies on stick-like structures called chromosomes.