Polymorphism of the HLA-DMA and DMB genes in rheumatoid arthritis.
OBJECTIVE
To determine whether the HLA-DMA and DMB genes, whose encoded molecules are involved in HLA class II-restricted antigen presentation, contribute to the genetic susceptibility to rheumatoid arthritis (RA).


METHODS
One hundred ninety-one RA patients, 147 control subjects, and 218 HLA-DRB1 genotype-matched control subjects were oligotyped for DMA and DMB genes.


RESULTS
DMA*0103 and DMB*0104 were significantly increased in the RA patients compared with the randomly selected and the matched controls, thus indicating a direct influence of the DM genes. After stratification of the patients and matched controls according to DRB1 genotypes, only DMA*0103 was increased in the RA patients with DRB1*01, as well as in the patients negative for the RA-susceptibility DR alleles.


CONCLUSIONS
Our results suggest that DMA*0103 could play an additional role in the genetic susceptibility to RA.
Pinet
V
V
Laboratoire d'Immunologie, INSERM U291, Montpellier, France.
Combe
B
B
Avinens
O
O
Caillat-Zucman
S
S
Sany
J
J
Clot
J
J
Eliaou
J F
JF
D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006681:HLA-D Antigens / Q000235:genetics*; D000949:Histocompatibility Antigens Class II; D006801:Humans; D011110:Polymorphism, Genetic
C416189:H2-M antigens; D006681:HLA-D Antigens; C084245:HLA-DM antigens; D000949:Histocompatibility Antigens Class II