What is (are) Multisystemic smooth muscle dysfunction syndrome ?
Multisystemic smooth muscle dysfunction syndrome is a disease in which the activity of smooth muscle throughout the body is impaired. This leads to widespread problems including blood vessel abnormalities, a decreased response of the pupils to light, a weak bladder, and weakened contractions of the muscles used for the digestion of food (hypoperistalsis). A certain  mutation in the ACTA2 gene has been shown to cause this condition in some individuals.