Role of CARD15, DLG5 and OCTN genes polymorphisms in children with inflammatory bowel diseases.
OBJECTIVE
To investigate the contribution of variants of CARD15, OCTN1/2 and DLG5 genes in disease predisposition and phenotypes in a large Italian cohort of pediatric patients with inflammatory bowel diseases (IBD).


METHODS
Two hundred patients with Crohn's disease (CD), 186 ulcerative colitis (UC) patients, 434 parents (217 trios), and 347 healthy controls (HC) were studied. Polymorphisms of the three major variants of CARD15, 1672C/T and -207G/C SNPs for OCTN genes, IGR2096a_1 and IGR2198a_1 SNPs for the IBD5 locus, and 113G/A variant of the DLG5 gene were evaluated. Potential correlations with clinical sub-phenotypes were investigated.


RESULTS
Polymorphisms of CARD15 were significantly associated with CD, and at least one variant was found in 38% of patients (15% in HC, OR = 2.7, P < 0.001). Homozygosis for both OCTN1/2 variants was more common in CD patients (1672TT 24%, -207CC 29%) than in HC (16% and 21%, respectively; P = 0.03), with an increased frequency of the TC haplotype (44.8% vs 38.3% in HC, P = 0.04). No association with the DLG5 variant was found. CD carriers of OCTN1/2 and DLG5 variants more frequently had penetrating disease (P = 0.04 and P = 0.01), while carriers of CARD15 more frequently had ileal localization (P = 0.03). No gene-gene interaction was found. In UC patients, the TC haplotype was more frequent (45.4%, P = 0.03), but no genotype/phenotype correlation was observed.


CONCLUSIONS
Polymorphisms of CARD15 and OCTN genes, but not DLG5 are associated with pediatric onset of CD. Polymorphisms of CARD15, OCTN, and DLG5 genes exert a weak influence on CD phenotype.
Cucchiara
S
S
Clinica Pediatrica, Università L Sapienza, Roma, Italy.
Latiano
A
A
Palmieri
O
O
Staiano
A M
AM
D'Incà
R
R
Guariso
G
G
Vieni
G
G
Rutigliano
V
V
Borrelli
O
O
Valvano
M R
MR
Annese
V
V
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D002648:Child; D004843:Epistasis, Genetic; D005260:Female; D005838:Genotype; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000235:genetics*; D007558:Italy; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D053473:Nod2 Signaling Adaptor Protein / Q000235:genetics*; D027701:Organic Cation Transport Proteins / Q000235:genetics*; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D000074058:Solute Carrier Family 22 Member 5; D027981:Symporters; D025521:Tumor Suppressor Proteins / Q000235:genetics*
C114461:DLG5 protein, human; D008565:Membrane Proteins; C429018:NOD2 protein, human; 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