DRB1*04 subtype in Thai patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) in a Thai population is significantly associated with HLA-DR4. The frequency of DR4 was 43 per cent in RA patients and 20 per cent in the healthy controls (p = 0.00008, OR = 3.06, 95% CI = 1.71, 5.52). To analyze which DR4 alleles were associated with the disease, the authors subtyped 52 DR4-positive RA patients compared to 28 DR4-positive healthy controls by amplification with DR4-specific primers followed by direct sequencing. Six DR4 alleles (DRB1*0401, *0403, *0404, *0405, *0406, and *0410) were found in the RA patient group while 5 alleles (DRB1*0401, *0403, *0405, *0406, and *0407) were found in the control group. Both groups were predominated by DRB11*0405, but there was a significant increase in the frequency of DRB1*0405 in DR4+ RA patients compared to DR4+ healthy controls (84.6% vs 46.4%, p = 0.0008, OR = 6.35, 95% CI = 1.96, 21.08). DR4 which shared epitope alleles (DRB1*0401, *0404, *0405) were observed in 47 (90.3%) DR4+ patients and 15 (53.5%) DR4+ controls (p = 0.0005, OR = 8.15, 95% CI = 2.29, 33.2). In addition, the authors found that DRB1*0403 was significantly decreased in DR4+ RA patients compared to controls (p = 0.0065, OR = 0.07, 95% CI = 0, 0.67).

HLA-DR types in rheumatic, congenital and degenerative cardiac valve diseasesin Saudi Patients

Subjects of Saudi origin were DNA typed for HLD-DR2, DR4 and DR[w]53 by fragment-length polymorphism and amplification by sequence-specific primer techniques based on polymerase chain reaction. Of these subjects, 125 sporadic heart valve disease [96 with rheumatic heart disease, 18 with degenerate and 11 with congenital degenerate valve disease] and 77 were healthy Saudi blood donors. While the frequency of individuals typed DR[4] was about the same in the rheumatic heart disease as in the control category [30% versus 23%, respectively], it was found to be higher [55%; P< 0.02], but below the level of marginal significance after correcting for the number of DR types, in the congenital degenerate valve category. No preferential association of any DR4 subtype could be detected. The incidence of DR2 was lower in the congenital cases compared to that in the controls [9% versus 21%] and remained about the same in the rheumatic heart disease patents as in the controls. The frequency of DR[w]53 in the degenerate valve categories was slightly lower than that in the controls, but the difference was not significant. The study failed to corroborate the association between HLA-DR4 and rheumatic heart disease shown in previous studies using the sterotyping approach

Human leucocyte antigen and insulin dependent diabetes mellitus.

HLA typing was done in 25 cases of insulin dependent diabetes mellitus (IDDM) and compared with 60 healthy controls. There was a significantly increased frequency of HLA B-8, HLA B-12 and HLA DR-3 in IDDMO. The odds ratio (relative risk) of developing IDDM for HLA B-8 was 4.42 (p less than 0.10), for HLA B-12 was 3.56 (p less than 0.10) and for HLA DR3 9.75 (p less than 0.001). There was no correlation of HLA specificity with complications of diabetes.