A common Ser/Thr polymorphism in the perforin-homologous region of human complement component C7.

Complement component C7 plays an important role in the formation of the membrane attack complex of the complement system. Here we describe a novel polymorphism of human C7, namely a nucleotide sequence polymorphism changing codon 367 from AGT (encoding Ser) to ACT (encoding Thr). Using the polymerase chain reaction, the polymorphism is easily detectable either as a MaeIII restriction fragment length polymorphism or by single-strand conformation analysis. The two alleles are both very common, probably in all major races.