Investigation of the Genetic Polymorphism Of Interleukin-10 Gene in Rheumatoid Arthritis Patients in Egypt
Rheumatoid arthritis is an inflammatory and considerably variable disease with both genetic and environmental factors contributing to the susceptibility to it as well as its severity. Two groups of Egyptian subjects were included; one group consisted of 54 clinically confirmed rheumatoid arthritis patients (Group I) and the other group consisted of 24 apparently healthy individuals (Group II). DNA was isolated from peripheral blood cells of both groups and genotyped by RFLP technique on IL-10 gene promoter. For rheumatoid arthritis patients, 5.5% were of the genotype AA and 40.7% were heterozygous (CA) while the remaining 53.7% were homozygous for the allele C. On the other hand, for the apparently healthy individuals, 15.3% were of the genotype AA and 15.3% were heterozygous (CA) while the remaining 61% were homozygous for the allele C. Statistically, there was a significant difference in the distribution of the genotype CA between rheumatoid arthritis patients and the apparently healthy individuals. This result suggests that the subjects with the genotype CA could be at more risk for developing rheumatoid arthritis than the subjects with other genotypes. This risk could not be attributed to the carriage of either allele A or C solely because the frequencies of A allele and C allele were not significantly different between the rheumatoid arthritis patients and apparently healthy individuals. Whether the-592 CA genotype of IL-10 implies a moderate Il-10 expression and a low efficiency to reduce inflammation in Egyptian subjects with rheumatoid arthritis needs further investigations.