Objective: To investigate whether the 3 most common mutations in the NOD2 gene that confer susceptibility to Crohn's disease (CD) are also associated with ankylosing spondylitis (AS).
Methods: DNA from 112 patients with AS and 168 controls of homogenous Spanish ancestry were studied. The frequencies of the pathogenic alleles of NOD2 (3020insC, 2722G>C, and 2104C>T) were determined by analysis of the melting curves after hybridization with FRET probes on a Light Cycler real-time polymerase chain reaction (PCR) system. Results. NOD2 allelic frequencies in controls (3020insC, 0.009; 2722G>C, 0.009; 2104C>T, 0.042) did not significantly differ from patients with AS (3020insC, 0.009; 2722G>C, 0.004; 2104C>T, 0.031).
Conclusion: The 3 most common CD NOD2 mutations do not contribute to disease susceptibility to AS, and therefore do not explain the susceptibility locus for AS in chromosome 16q.