CD209 in inflammatory bowel disease: a case-control study in the Spanish population.
BACKGROUND
The etiology of Ulcerative Colitis (UC) and Crohn's Disease (CD), considered together as Inflammatory Bowel Diseases (IBD), involves environmental and genetic factors. Although some genes are already known, the genetics underlying these diseases is complex and new candidates are continuously emerging. The CD209 gene is located in a region linked previously to IBD and a CD209 functional polymorphism (rs4804803) has been associated to other inflammatory conditions. Our aim was to study the potential involvement of this CD209 variant in IBD susceptibility.


METHODS
We performed a case-control study with 515 CD patients, 497 UC patients and 731 healthy controls, all of them white Spaniards. Samples were typed for the CD209 single nucleotide polymorphism (SNP) rs4804803 by TaqMan technology. Frequency comparisons were performed using chi2 tests.


RESULTS
No association between CD209 and UC or CD was observed initially. However, stratification of UC patients by HLA-DR3 status, a strong protective allele, showed that carriage of the CD209_G allele could increase susceptibility in the subgroup of HLA-DR3-positive individuals (p = 0.03 OR = 1.77 95% CI 1.04-3.02, vs. controls).


CONCLUSIONS
A functional variant in the CD209 gene, rs4804803, does not seem to be influencing Crohn's disease susceptibility. However, it could be involved in the etiology or pathology of Ulcerative Colitis in HLA-DR3-positive individuals but further studies are necessary.
Núñez
Concepción
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Servicio de Inmunología Clínica, Hospital Clínico San Carlos, Madrid, Spain. conchita.npardo@gmail.com
Oliver
Javier
J
Mendoza
Juan Luis
JL
Gómez-García
María
M
Taxonera
Carlos
C
Gómez
Luis M
LM
López-Nevot
Miguel A
MA
de la Concha
Emilio G
EG
Urcelay
Elena
E
Martínez
Alfonso
A
Martín
Javier
J
D000328:Adult; D016022:Case-Control Studies; D015815:Cell Adhesion Molecules / Q000235:genetics*; D016009:Chi-Square Distribution; D003093:Colitis, Ulcerative / Q000235:genetics*; D003424:Crohn Disease / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006684:HLA-DR Antigens / Q000235:genetics; D006801:Humans; D037181:Lectins, C-Type / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011956:Receptors, Cell Surface / Q000235:genetics*; D013030:Spain; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
D015815:Cell Adhesion Molecules; D005819:Genetic Markers; D006684:HLA-DR Antigens; D037181:Lectins, C-Type; D011956:Receptors, Cell Surface; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin