Phenotypic expansion of visceral myopathy associated with ACTG2 tandem base substitution

Eur J Hum Genet. 2015 Dec;23(12):1679-83. doi: 10.1038/ejhg.2015.49. Epub 2015 Mar 18.


Familial visceral myopathy (FVM) is a rare heritable and heterogeneous condition due to impaired smooth muscle function. We identified a family segregating 11 individuals with a spectrum of visceral symptoms involving the small intestine, colon, biliary tract, urinary tract and uterus. Whole-exome sequencing revealed a novel heterozygous tandem base substitution c.806_807delinsAA (p.(Gly269Glu)) in ACTG2, encoding smooth muscle actin γ-2, in affected family members. Variants in ACTG2 were recently identified in FVM with intestinal pseudo-obstruction as well as with the congenital megacystics-microcolon-intestinal hypoperistalsis syndrome. In our family, eight affected members presented with severe complications from the biliary and/or the urinary tracts in addition to gastrointestinal pseudo-obstructions. Furthermore, all affected mothers had a history of assisted deliveries owing to poor progress during labor and weak uterine contractions. The variable involvement of multiple smooth muscle-dependent organs in our family, including the biliary tract and the uterus, add to the phenotypic spectrum associated with ACTG2 missense variants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / chemistry
  • Actins / genetics*
  • Adolescent
  • Adult
  • Amino Acid Sequence
  • Child
  • Duodenum / abnormalities*
  • Female
  • Humans
  • Intestinal Pseudo-Obstruction / diagnosis
  • Intestinal Pseudo-Obstruction / genetics*
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Mutation, Missense*
  • Pedigree
  • Phenotype*
  • Urinary Bladder / abnormalities*


  • ACTG2 protein, human
  • Actins

Supplementary concepts

  • Visceral Myopathy, Familial