Three CARD15 mutations (SNP8, SNP12, SNP13) were significantly associated with CD, however ethnic variations and genotype-phenotype relationships are still to be defined.
Aims: To evaluate the prevalence of three CARD15 mutations in 91 in-out consecutive CD, 109 Ulcerative Colitis (UC), 101 healthy controls; to examine the genotype-phenotype relationships among italian pts with CD.
Material and methods: The three mutations were determined by direct sequencing analysis. In CD were evaluated several feature of disease phenotype. Data analysis was performed by using c2 or Fisher Test applying Bonferroni's correction.
Results: The allelic and genotype frequencies of CARD15 mutations were significantly associated to CD. None of controls or UC were homozygotes (OM) or compound heterozigotes (CET). In CD the carriers of at least one mutation were 26/91 (28.6%). The frequencies of simple heterozygotes (ET), CET and OM were: 19/26, 4/26, 3/26 respectively. A significant positive association was found between small bowel location and an acute intestinal obstruction at diagnosis and the carriers of at least one mutation (p = 0.036, OR:0.33 [0.12-0.9] and p = 0.0025, OR:0.125 [0.03-0.5], respectively), particularly with OM and CET genotype (p = 0.005, OR:0.07 [0.01-0.6]). A positive trend between the number of surgery and the carriers of at least one mutation was found, but it didn't reach statistical significance (p = 0.0469, OR:0.3 [0.1-0.96]). No relationship between CARD15 mutations and the other phenotype characteristics was found.
Conclusions: Our data confirms that CARD15 mutations are significantly associated with CD also in Italian population and with small bowel location (OM and CET genotype). A new positive association was also found between the carriers of at least one mutation and the acute intestinal obstruction at diagnosis.