Genetics and gastroenterology.

The decade since the last review of this subject in Gut has seen considerable advances in many aspects of genetics, including the influence of heredity on disease. Compared with some specialties gastroenterology has few disorders with simple Mendelian inheritance, but in most of its conditions there is some hereditary influence. Some of the best human data illustrating a quantitative type of disease liability are those on hypertrophic pyloric stenosis and Hirschsprung's disease, and the discovery of two of the genes of the genotype giving susceptibility to duodenal ulcer is still unique. There is growing realization that both heredity and environmental factors are concerned in the aetiology of most disorders.