Complement polymorphism in Greece.

The polymorphisms of the complement components C2, C3, C4 and BF have been studied in a sample of 166 unrelated individuals from Northern Greece. The C3F and BFF allele frequencies of Greeks are within the range of frequencies reported from Europe. A single individual with a rare heterozygote variant C2C/C2A was found in Greeks. This C2*A allele was found for the first time in European Caucasoids. For the C4 system six different alleles were found at both C4A and C4B loci. There were a low frequency of the null alleles at the C4A locus and a relatively high incidence of gene duplications in this system.