COMPLEMENT POLYMORPHISM IN HERPES-GESTATIONIS - ASSOCIATION WITH C4 NULL ALLELE

Background. Herpes gestationis (HG) is a rare, pregnancy-related skin disease characterized by the production of an autoantibody to a compon ent of the hemidesmosome. It is associated with the class II antigens HLA-DR3 and HLA-DR4, but its potential association with the ''class II I antigens'' C2, C4, and factor B has not previously been studied. Obj ective. Our purpose was to study complement polymorphism in HG. Method s. Using electrophoresis and immunofixation techniques, we determined the allele frequencies of C4A, C4B, C3, and factor B in 42 patients wi th a history of HG. Results. Ninety percent of patients carried a C4 n ull allele (C4QO). No statistically significant association with C3 o r factor B alleles was seen. Conclusion: HG is associated with the pre sence of a C4QO. Whether the C4*QO is the primary genetic association , or whether the C4QO is related to its linkage disequilibrium with D R3 and DR4 has yet to be determined.