The absence of ganglion cells in Hirschsprung's disease.
D003106:Colon / Q000294:innervation* / Q000473:pathology; D005725:Ganglia, Autonomic; D006801:Humans; D008531:Megacolon / Q000473:pathology* / Q000503:physiopathology; D009130:Muscle, Smooth / Q000294:innervation