ABSTRACT
To assess the relationship between HLA-DRB1 and rheumatoid arthritis in Egyptian patients, 40 subjects ere examined; 26 were rheumatoid arthritis patients and 14 were normal persons. The patients were further subdivided into groups according to the Mean Grades of the Disease Activity. All patients and the controls were subjected to ESR estimation by Westgren's method, Rheumatoid factor testing and HLA-DRB1 typing by PCR. The DNA was extracted from whole blood. Exon 2 was amplified and checked by gel electrophoresis. For HLA-DRB1 allele detection, amplification products were subsequently hybridized using typing strips in which 37 sequence specific DNA probe lines and 2 control lines were fixed. There was a significant association between rheumatoid factor and the grade of disease activity. There was a significant association between HLA-DRB1 broad types *4 and *1 and the susceptibility to rheumatoid arthritis. HLA-DRB1 broad types *4 and *1 had significant higher frequencies in patients than controls. They were 40.4% and 21.2% in patients while were 10.7% and 3.6% in controls. P values were 0.04 and 0.003 respectively for them. HLA-DRB1 *0102 allele had shown a significant increase in group IV rheumatoid arthritis patients with a frequency of 50%. high relative risk, and a P value of 0.014