The genetics of Crohn disease: Complex segregation analysis of a family study with 265 patients with Crohn disease and 5,387 relatives

Abstract

We have analysed the pedigrees of 265 probands with Crohn disease, collected from a specialty clinic at the University of Düsseldorf. Complex segregation analysis suggests the presence of a recessive gene with incomplete penetrance for susceptibility to the disease with no residual causes of family resemblance. However, a proportion of the isolated cases are probably due to phenocopies, this proportion being greatest among cases with an advanced age of onset.