Characterization of the FcgammaRIIA promoter and 5'UTR sequences in patients with systemic lupus erythematosus.

FcgammaRIIA is a candidate gene involved in the predisposition to systemic lupus erythematosus (SLE). The presence of low binding alleles in patients with SLE is not sufficient to explain the lower phagocytic capacity observed in SLE patients. We considered the possibility that nucleotide polymorphisms in the FcgammaRIIA promoter that cause alterations in receptor expression might be present in SLE patients. In the present study, a 2.0 kb region of the human FcgammaRIIA 5'UTR from 20 normal donors and 53 SLE patients was examined. The results demonstrate that the sequence of the human FcgammaRIIA 5' region differs from the published sequence. Two novel SNPs have been identified in the distal region of the FcgammaRIIA promoter. The polymorphisms are present in both disease-free and SLE donors and do not associate with quantitative changes in FcgammaRIIa phagocytic function.