The IBD2 locus shows linkage heterogeneity between ulcerative colitis and Crohn disease

Am J Hum Genet. 2000 Dec;67(6):1605-10. doi: 10.1086/316905. Epub 2000 Nov 10.


The IBD2 locus on chromosome 12 has been linked to both Crohn disease (CD) and ulcerative colitis (UC) but has not been detected in some CD-dominated data sets. In the present study, we genotyped 581 relative pairs with inflammatory bowel disease (252 from CD-only families, 138 from UC-only families, and 191 from mixed families containing cases of both CD and UC), using 12 markers spanning the IBD2 locus. A GENEHUNTER-PLUS multipoint LOD score of 3.91 was detected for pairs from UC-only families, compared with 1.66 for CD-only and 1.29 for mixed families. The difference between the LOD scores for UC and CD was significant in two different tests for heterogeneity (P=.0057 for one test and P=.0375 for the other). IBD2 thus appears to make a major contribution to UC susceptibility but to have only a relatively minor effect with regard to CD, for which there may be substantially more locus heterogeneity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alleles
  • Chromosome Mapping
  • Chromosomes, Human, Pair 12 / genetics
  • Colitis, Ulcerative / genetics*
  • Computer Simulation
  • Crohn Disease / genetics*
  • Genetic Heterogeneity*
  • Genetic Linkage / genetics*
  • Genetic Predisposition to Disease / genetics
  • Heterozygote
  • Humans
  • Lod Score
  • Matched-Pair Analysis
  • Microsatellite Repeats / genetics
  • Nuclear Family
  • Software
  • Statistics, Nonparametric
  • United Kingdom
  • United States