Association of two loci on chromosome 2q with nodal osteoarthritis.

OBJECTIVE To search for genetic association between microsatellite marker loci and sibling pairs with nodal osteoarthritis (NOA). METHODS Using the affected sibling pair method of analysis, genomic DNA from 66 sib pairs with NOA was analysed for association with highly polymorphic microsatellite marker loci. The microsatellite markers were amplified using polymerase chain reaction and typed on polyacrylamide gels. RESULTS A significant association (p < 0.05) was identified between NOA and two loci on the short arm of chromosome 2 (2q 23-35). Candidate genes for osteoarthritis in this region include: fibronectin, a glycoprotein present in the extracellular matrix of normal cartilage; the alpha 2 chain of collagen type V, a major constituent of bone; and the interleukin-8 receptor, important in the regulation of neutrophil activation and chemotaxis. CONCLUSIONS The chromosomal region 2q 23-35 requires further detailed study in NOA. Confirmation of these findings in large independent data sets and further analysis of candidate genes in this region will be important in unravelling the molecular basis for this common disease.