Objective: To determine whether dysfunctional or deficient mannose-binding protein (MBP) variants are found with increased frequency in black patients with systemic lupus erythematosus (SLE) compared with controls.
Methods: Allele-specific polymerase chain reaction amplification of 4 different polymorphic sites was performed on samples from 92 black SLE patients and 86 geographically matched black controls.
Results: Two structural polymorphisms of MBP, associated with low serum levels of MBP, were found with significantly increased frequency in the SLE patient population compared with controls. In contrast, a promoter haplotype associated with particularly high serum levels of MBP was negatively associated with SLE.
Conclusion: Deficiencies of MBP predispose individuals to SLE.