GENETIC-VARIATION IN THE INTERLEUKIN-10 GENE PROMOTER AND SYSTEMIC LUPUS-ERYTHEMATOSUS

Objective. To investigate interleukin 10 (IL-IO) gene promoter polymor phisms in systemic lupus erythematosus (SLE) and its clinical subsets. Methods. DNA from 76 Caucasian patients with SLE and 119 controls as genotyped for 3 defined dimorphic polymorphisms (C or A at position -1 082, C or T at position -819, C or A at position -592) in the promoter region of the IL-10 gene, using the polymerase chain reaction to ampl ify the IL-IO gene promoter and oligonucleotide probes specific for ea ch allelic sequence. The frequency of genotypes was compared between p atients with SLE and controls, and between clinical subsets of patient s with the disease. Results. There was no significant change in the al lele frequency of the three IL-10 gene promoter dimorphic polymorphism s in the SLE group compared with controls. However. when subgrouped ac cording to autoantibody status and clinical features, IL-10 -1082G, - 819C, and -592*C alleles were increased in patients possessing Po aut oantibodies and those with renal involvement. These alleles are in pre ferential allelic association. namely GCC, ACC, and ATA haplotypes, an d the GCC haplotype was increased in these patient subgroups. Conclusi on. Polymorphisms within the IL-10 gene promoter that are associated w ith high IL-10 levels may be important in the development of certain c linical features in SLE.