Tuokko J, Koskinen S, Westman P, Yli-Kerttula U, Toivanen A, Ilonen J
Turku Immunology Centre and Department of Medical Microbiology, University of Turku, Finland.
Br J Rheumatol. 1998 Nov;37(11):1203-6. doi: 10.1093/rheumatology/37.11.1203.
The purpose was to study tumour necrosis factor (TNF)-a, -b and -c microsatellites as potential new susceptibility markers for reactive arthritis (ReA). Fifty-nine patients typed for HLA-B27 were studied for frequencies of TNF microsatellite alleles and compared with allele frequencies determined from 285 random haplotypes and 46 healthy HLA-B27-positive controls. TNFa, -b and -c microsatellite sequences were amplified by the polymerase chain reaction, and the size of the product was defined by an automated sequencer. The frequencies of TNFa6 and -c1 alleles were found to be increased in patients with ReA, whereas TNFa11 and -c2 frequencies were decreased as compared to control haplotypes. The increase in the c1 allele in patients with ReA independently from HLA-B27 suggests that it might be a new susceptibility marker for the disease. The association of ReA with other alleles was due to a linkage disequilibrium with HLA-B27.
