The association of congenital abnormalities and gastrointestinal tract diseases has been described. The coincidence of Down's syndrome and coeliac disease has been occasionally reported, but a clear relation is not definitely established. Reviewing 190 patients with coeliac disease diagnosed at Queen Elizabeth Hospital, London, from 1960 to 1985 an increased incidence of Down's syndrome compared to the natural incidence of this abnormality in the general population was found. The age of the mothers was well below that where a reverse in the incidence of Down's syndrome is expected, and it appears therefore that this anomaly and coeliac disease may be linked. This possibility should be bourne in mind when evaluating children with Down's syndrome and gastrointestinal symptoms.