Evidence map›Paper›PMID 42018767›Full record

ArticleJournal of Crohn's & colitis2026

Heritability of Crohn's disease and ulcerative colitis: a Swedish nationwide population-based twin study.

Olle Grännö, Joel Thunberg, Jonas F Ludvigsson, Ralf Kuja-Halkola, Carl Mårten Lindqvist, Jonas Halfvarson

Abstract readTwin Study
In one paragraph

Article in Journal of Crohn's & colitis, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Olle GrännöDepartment of Laboratory Medicine, Clinical Microbiology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.ORCID 0000-0002-4329-1659
Joel ThunbergDepartment of Gastroenterology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
Jonas F LudvigssonDepartment of Medical Epidemiology and Biostatistics, Karolinska Institutet, Solna, Sweden.ORCID 0000-0003-1024-5602
Ralf Kuja-HalkolaDepartment of Medical Epidemiology and Biostatistics, Karolinska Institutet, Solna, Sweden.ORCID 0000-0002-3765-2067
Carl Mårten LindqvistFaculty of Medicine and Health, School of Medical Sciences, Örebro University, Örebro, Sweden.ORCID 0000-0003-3887-9519
Jonas HalfvarsonDepartment of Gastroenterology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.ORCID 0000-0003-0122-7234

Funding

ALF agreement OLL-961742Örebro University Hospital Research Foundation OLL-986849Swedish Research Council 2020-02021Swedish Research Council 2025-02685Swedish state under the agreement between the Swedish government and the county councils
6 · The paper itself

Abstract

BACKGROUND AND

aimsLimited statistical power has hampered previous estimates of concordance between relatives and heritability in inflammatory bowel diseases (IBD). To examine the genetic component of Crohn's disease and ulcerative colitis, we established the largest nationwide IBD twin cohort to date and assessed estimates of concordance and heritability.

methodsWe used the Swedish Twin Registry to identify all twins from complete pairs with known zygosity born between 1886 and 2004. The Swedish National Patient Register was used to identify all patients diagnosed with IBD. We calculated proband concordance rates and fitted a model estimating explained variance in diseases due to genetics (ie, the heritability), environment shared between twins, and environment unique to each twin.

resultsA cohort of 111 080 twins was followed until a median age of 62.2 years, during which 964 individuals were diagnosed with IBD. The proband concordance rate for Crohn's disease was 0.30 in monozygotic pairs and 0.02 in dizygotic pairs. The corresponding rates for ulcerative colitis were 0.15 and 0.03. After adjusting for sex and birth year, heritability was estimated to be 0.78 (95% CI: 0.68-0.87) for Crohn's disease and 0.57 (95% CI: 0.46-0.69) for ulcerative colitis.

conclusionIn this large population-based twin study, the heritability of Crohn's disease was 0.78 and 0.57 for ulcerative colitis. These findings highlight the disparity between heritability estimates from twin studies and those inferred from genome-wide association studies, underscoring the need for continued exploration of the genetic basis of IBD.

Indexed as

Colitis, UlcerativeCrohn DiseaseDiseases in TwinsAdultAgedFemaleGenetic Predisposition to DiseaseHumansMaleMiddle AgedRegistriesSwedenTwins, DizygoticTwins, Monozygoticheritabilityinflammatory bowel diseasetwin study

Identifiers

PMID42018767
PMCPMC13102174

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.