Hirschsprung disease

Hirschsprung disease is characterized by both incomplete penetrance and variable expression. Incomplete penetrance means that some people with a gene change or mutation associated with Hirschsprung disease (HSCR) do not have HSCR. Variable expression means that people with a gene change or mutation may have different symptoms than others with the same change or mutation. Genes are the basic unit of heredity. Genes are made of DNA and are instructions to make proteins and molecules inside the cells that make up the body. If you have further questions about variable expression and incomplete penetrance in Hirschsprung disease speak with your physican or a genetic counselor. To locate a genetic counselor near you use the Find a Genetic Counselor tool on the National Society of Genetic Counselors website.