Hirschsprung disease
Inheritance
Are there forms of Hirschsprung disease that aren't genetic?
There are forms of Hirschsprung disease that are sporadic, or not inherited. The diagnosis of sporadic Hirschsprung disease means there are probably multiple factors that contribute to causing Hirschsprung disease, not just one gene.
http://omim.org/entry/600155
"Hirschsprung Disease Overview" GeneReviews. 01 Oct. 2015. Web. 14 Jun. 2016. http://www.ncbi.nlm.nih.gov/books/NBK1439/