Genome-wide association study for Crohn's disease in the Quebec Founder Population identifies multiple validated disease loci.
Genome-wide association (GWA) studies offer a powerful unbiased method for the identification of multiple susceptibility genes for complex diseases. Here we report the results of a GWA study for Crohn's disease (CD) using family trios from the Quebec Founder Population (QFP). Haplotype-based association analyses identified multiple regions associated with the disease that met the criteria for genome-wide significance, with many containing a gene whose function appears relevant to CD. A proportion of these were replicated in two independent German Caucasian samples, including the established CD loci NOD2 and IBD5. The recently described IL23R locus was also identified and replicated. For this region, multiple individuals with all major haplotypes in the QFP were sequenced and extensive fine mapping performed to identify risk and protective alleles. Several additional loci, including a region on 3p21 containing several plausible candidate genes, a region near JAKMIP1 on 4p16.1, and two larger regions on chromosome 17 were replicated. Together with previously published loci, the spectrum of CD genes identified to date involves biochemical networks that affect epithelial defense mechanisms, innate and adaptive immune response, and the repair or remodeling of tissue.
Raelson
John V
JV
Genizon BioSciences, Inc., St. Laurent, QC, Canada H4T 2C7. john.raelson@genizon.com
Little
Randall D
RD
Ruether
Andreas
A
Fournier
Hélène
H
Paquin
Bruno
B
Van Eerdewegh
Paul
P
Bradley
W E C
WE
Croteau
Pascal
P
Nguyen-Huu
Quynh
Q
Segal
Jonathan
J
Debrus
Sophie
S
Allard
René
R
Rosenstiel
Philip
P
Franke
Andre
A
Jacobs
Gunnar
G
Nikolaus
Susanna
S
Vidal
Jean-Michel
JM
Szego
Peter
P
Laplante
Nathalie
N
Clark
Hilary F
HF
Paulussen
René J
RJ
Hooper
John W
JW
Keith
Tim P
TP
Belouchi
Abdelmajid
A
Schreiber
Stefan
S
D000483:Alleles; D002886:Chromosomes, Human, Pair 17; D002893:Chromosomes, Human, Pair 3; D002894:Chromosomes, Human, Pair 4; D003424:Crohn Disease / Q000235:genetics* / Q000473:pathology; D018703:Founder Effect; D005602:France / Q000208:ethnology; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D005828:Genetics, Population; D015894:Genome, Human; D006239:Haplotypes; D006801:Humans; D053473:Nod2 Signaling Adaptor Protein / Q000235:genetics; D020161:Physical Chromosome Mapping; D011792:Quebec; D018123:Receptors, Interleukin / Q000235:genetics; D015203:Reproducibility of Results; D012307:Risk Factors