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[Alleles of the major histocompatibility system associated with susceptibility to the development of Takayasu's arteritis].

OBJECTIVE
Since 1972, the relationship between HLA alleles and the susceptibility for Takayasu arteritis (TA) has been studied on different populations. Hence the results up to date are heterogeneous, the objective of the present review is to analyze the relationship between the presence of HLA alleles and the susceptibility for the development of TA considering the ethnic origin of the studied populations.


MATERIAL AND METHODS
We carried out a bibliographic review from clinical articles of case and controls studies on different populations on which the relationship between HLA alleles and the susceptibility for TA was studied, published since 1972 until February 2000.


RESULTS
We reviewed articles of studies on Asian, Arab, North-American and Mexican Mestizo populations. On Asian populations TA was associated with HLA-A31, -B52, -B39, -B5 and -DR2, on Arabs with HLA-A2, -A9, -B35 and -DR7, on North-Americans with HLA-DR4 and on Mexican Mestizo with HLA-B5, -B52 and -DR6. On the other hand, recent reports establish that several HLA-B alleles (HLA-B52 and HLA-B39) associated with the disease share some residues important on the antigen presentation.


CONCLUSIONS
Hence the heterogeneity of the results obtained up to date, it stands out the increase on HLA-B52 and HLA-DR4 reported on ethnically different populations. More recent data point the possible participation of an epitope located on the peptide-binding site of the HLA-B molecule (positions 63 and 67) that seems to be shared by several alleles associated with the disease. These residues might be participating on the presentation of an unknown antigen that would unchain the disease on the genetically susceptible individuals group.