title: Pediatric inflammatory bowel disease: clinical and molecular genetics.
abstract: Pediatric-onset inflammatory bowel disease (IBD) is characterized by distinct phenotypic differences compared to adult-onset IBD. This raises the question whether early (pediatric) onset IBD represents the same disease process occurring in adults but merely at an earlier age or does IBD in children have a very different etiology and pathogenesis but with the same clinical presentation as adults. The use of techniques such as whole genome association studies to perform broad, unbiased screening for the contributions of common genetic variations to complex disease has rapidly assisted in the identification of several novel susceptibility loci associated with pediatric-onset Crohn's disease such as IL23R and ATG16L1. These genes join the already confirmed IBD susceptibility genes such as NOD2/CARD15, IBD5, and DLG5. Therefore, there is hope that advances in the field of clinical and molecular genetics will assist in answering the fundamental question of whether pediatric IBD has a different etiology and pathogenesis compared to adult IBD. This review examines the current status of clinical and molecular genetics of pediatric IBD, and highlights the differences between pediatric and adult IBD in disease phenotypes and genotypes. Finally, the future directions of genetic investigations in pediatric IBD are discussed.
authors.affiliation: Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
authors.forename: Vincent
authors.initials: V
authors.lastname: Biank
authors.forename: Ulrich
authors.initials: U
authors.lastname: Broeckel
authors.forename: Subra
authors.initials: S
authors.lastname: Kugathasan
mesh_terms: D002648:Child; D020022:Genetic Predisposition to Disease; D006801:Humans; D007109:Immunity / Q000235:genetics; D015212:Inflammatory Bowel Diseases / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics; D053473:Nod2 Signaling Adaptor Protein / Q000235:genetics; D027701:Organic Cation Transport Proteins / Q000235:genetics; D000074058:Solute Carrier Family 22 Member 5; D027981:Symporters; D025521:Tumor Suppressor Proteins / Q000235:genetics; D018433:Twin Studies as Topic
chemical_list: C114461:DLG5 protein, human; D008565:Membrane Proteins; D053473:Nod2 Signaling Adaptor Protein; D027701:Organic Cation Transport Proteins; C109807:SLC22A4 protein, human; C492020:SLC22A5 protein, human; D000074058:Solute Carrier Family 22 Member 5; D027981:Symporters; D025521:Tumor Suppressor Proteins