The cytotoxic T-lymphocyte antigen 4 (CTLA4, CD152) gene is a positional and functional candidate gene to susceptibility to systemic lupus erythematosus (SLE) because CTLA4 gene maps in the described SLE risk region 2q33 and CTLA4 molecule has an inhibitory effect on T-cell activation. Several polymorphisms have been described in CTLA4 gene, among them, a T/C change at position -1722, a C/T transition at position -319, and another A/G transition at position +49. The aim of this study was to investigate the possible association of these polymorphisms with the susceptibility to SLE in 276 Spanish autochthonous patients using a healthy control group composed of 194 ethnically matched volunteer bone marrow donors. Genotyping of these CTLA4 positions was performed in SLE patients and controls using a polymerase chain reaction amplification refractory mutation system. The genotypic frequencies were in Hardy-Weinberg equilibrium in all patients. No differences in the distribution of the genotype frequencies between patients and controls were found in any case. Our results from the Spanish autochthonous population differ from those found in the Korean population regarding the involvement of the polymorphism located at -1722 in the susceptibility to SLE.