Background and purpose: The fractalkine ligand/receptor (CX3CL1/CX3CR1) complex is important in inflammatory responses and has been associated with vascular disease. We determined whether genetic variants in CX3CL1 and CX3CR1 are associated with carotid atherosclerosis in 2 large European populations.
Methods: 18 polymorphisms in CX3CL1 and CX3CR1 were genotyped in 2763 German community individuals (CAPS). Positive results were tested for replication on 6049 French community individuals (3C Study).
Results: In CAPS we found associations of common carotid artery (CCA)-IMT with 2 CX3CL1 (rs170364, rs614230) and 1 CX3CR1 (rs3732378) variants, and significant interactions of CX3CR1 rs11129820, rs3732378, and rs614230 variants with smoking and alcohol consumption in relation with CCA-IMT. None of these were replicated in 3C. In 3C only there was a borderline significant association of rs3732378 with carotid plaques.
Conclusions: In almost 9000 subjects, we found no replicable associations of CX3CL1 and CX3CR1 polymorphisms with CCA-IMT or plaque.