Molecular analysis of HLA-DR in seronegative polyarticular juvenile rheumatoid arthritis with polymerase chain reaction (PCR)‎ and oligonucleotide probes

الملخص EN

This work aimed at the determination of HLA-DRB genes and their different alleles associated with seronegative juvenile rheumatoid arthritis (JRA) and the relationship of these genes in influencing the clinical expression of such disease.

Subjects and methods : Twenty polyarticular JRA patients [negative for rheumatoid factor (R.F) and antinuclear antibodies (ANA)] were included.

They were 12 males and 8 females.

Their mean age ± SD was 12.5 ± 3.95 years and mean disease duration ± SD was 4.45 ± 2.7 years.

Also twenty-four apparently healthy children matched for age and sex, were selected as controls.

Patients and controls were subjected to HLA-DR genotyping usings a reverse hybridization line probe assay “reversed dot blot technique”.

Results : HLA DR8 was present in 49.3 % of patients as compared to 19.1 % in the control group.

This difference was statistically significant [p = 0.0428, relative risk (RR) = 4.09].

As far as suballeles, it was also found that HLA DRB1* 0801 was significantly higher in the patients than the control group (34.3 % vs 2.1 % in controls, p = 0.0410, RR = 16.032).

Another significant association was observed for HLADRB3* 0202 which was higher in patients than controls 35.47vs 3.1, p = 0.0427, RR = 16.058).

On the other hand, HLA-DRB1* 0701 was lower in patients (4.1 %) as compared to controls (26.5 %) and their difference was statistically significant (p = 0.035 and RR = 0.111).

Conclusion : Detection of HLA genes and their different alleles with oligonucleotide probes provides more precise disease susceptibility markers that may have clinical relevance as a predictor for JRA subtypes.