Association of HLA-DR4-Dw15 (DRB1*0405) and DR10 with rheumatoid arthritis in a Spanish population.
OBJECTIVE
To analyze the associations of HLA class II antigens with rheumatoid arthritis (RA) in a Spanish population.


METHODS
We used DNA oligotyping to determine DR types, DQA1 and DQB1 alleles, and DR4 variants in 70 unrelated seropositive RA patients and 189 healthy controls living in Spain.


RESULTS
A significantly higher frequency of DR4 was seen in RA patients compared with controls (relative risk [RR] = 2.40). The DR10 specificity correlated most strongly with disease susceptibility (RR = 3.84). A significant decrease in the frequency of DR7 was observed in the RA patients (RR = 0.48). DR4-Dw15 (DRB1*0405) was found to be the unique DR4 allele associated with RA (RR = 4.27, P < 0.05), whereas Dw4 (DRB1*0401) and Dw14 (DRB1*0404/0408) showed no association, and both Dw10 (DRB1*0402) and Dw13 (DRB1*0403/0407) were negative risk factors for the disease. Approximately one-third of the cases of RA could not be explained by the "shared epitope" hypothesis. Investigation of the DQ alleles associated with DR4 showed that the haplotype Dw15-DQ8 (DRB1*0405-DQB1*0302) was a susceptibility factor for RA (RR = 6.36, P < 0.05).


CONCLUSIONS
Our results suggest that HLA class II alleles involved in RA susceptibility can vary among different Caucasian populations.
Immunology Service, Hospital Universitario Virgen del Rocío, Seville, Spain.
J
J
Yelamos
J R
JR
Garcia-Lozano
I
I
Moreno
I
I
Aguilera
M F
MF
Gonzalez
A
A
Garcia
A
A
Nuñez-Roldan
B
B
Sanchez
D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000453:epidemiology / Q000276:immunology*; D006681:HLA-D Antigens / Q000032:analysis* / Q000097:blood / Q000235:genetics; D006684:HLA-DR Antigens / Q000032:analysis* / Q000097:blood / Q000235:genetics; D015804:HLA-DR4 Antigen / Q000032:analysis* / Q000097:blood / Q000235:genetics; D006801:Humans; D008875:Middle Aged; D013030:Spain / Q000453:epidemiology
D006681:HLA-D Antigens; D006684:HLA-DR Antigens; D015804:HLA-DR4 Antigen