title: Penetrance of Congenital Heart Disease in a Mouse Model of Down Syndrome Depends on a Trisomic Potentiator of a Disomic Modifier.
abstract: Down syndrome (DS) is a significant risk factor for congenital heart disease (CHD), increasing the incidence 50 times over the general population. However, half of people with DS have a normal heart and thus trisomy 21 is not sufficient to cause CHD by itself. Ts65Dn mice are trisomic for orthologs of >100 Hsa21 genes, and their heart defect frequency is significantly higher than their euploid littermates. Introduction of a null allele of Creld1 into Ts65Dn increases the penetrance of heart defects significantly. However, this increase was not seen when the Creld1 null allele was introduced into Ts1Cje, a mouse that is trisomic for about two thirds of the Hsa21 orthologs that are triplicated in Ts65Dn. Among the 23 genes present in three copies in Ts65Dn but not Ts1Cje, we identified Jam2 as necessary for the increased penetrance of Creld1-mediated septal defects in Ts65Dn. Thus, overexpression of the trisomic gene, Jam2, is a necessary potentiator of the disomic genetic modifier, Creld1 No direct physical interaction between Jam2 and Creld1 was identified by several methods. Regions of Hsa21 containing genes that are risk factors of CHD have been identified, but Jam2 (and its environs) has not been linked to heart formation previously. The complexity of this interaction may be more representative of the clinical situation in people than consideration of simple single-gene models.
authors.affiliation: Department of Physiology and Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: Huiqing
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Physiology and Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: Sarah
authors.initials: S
authors.lastname: Edie
authors.affiliation: Department of Physiology and Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: Donna
authors.initials: D
authors.lastname: Klinedinst
authors.affiliation: Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 High-Throughput Biology Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: Jun Seop
authors.initials: JS
authors.lastname: Jeong
authors.affiliation: High-Throughput Biology Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: Seth
authors.initials: S
authors.lastname: Blackshaw
authors.affiliation: Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon 97239.
authors.forename: Cheryl L
authors.initials: CL
authors.lastname: Maslen
authors.affiliation: Department of Physiology and Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 rreeves@jhmi.edu.
authors.forename: Roger H
authors.initials: RH
authors.lastname: Reeves
mesh_terms: D000818:Animals; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism; D004314:Down Syndrome / Q000235:genetics* / Q000473:pathology; D004843:Epistasis, Genetic; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism; D060045:Genes, Modifier; D006330:Heart Defects, Congenital / Q000235:genetics* / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D019683:Penetrance; D014314:Trisomy; D015027:Zebrafish; D062765:Junctional Adhesion Molecule B
chemical_list: D015815:Cell Adhesion Molecules; D016326:Extracellular Matrix Proteins; C000588446:CRELD1 protein, mouse; C498781:Jam2 protein, mouse; D062765:Junctional Adhesion Molecule B
keywords: Down syndrome; congenital heart disease; disomic modifier; trisomic potentiator