Complement component C3: molecular basis of the C3*S025 variant and evidence for molecular heterogeneity of other variants.
Complement component 3 (C3) is the central molecule of the complement system. It displays a number of polymorphic variants with, as yet, unclear functional consequences. We have investigated a number of rare C3 variants by PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) analysis and could identify the molecular basis of a C3*S025 variant. The decreased electrophoretic mobility of this protein is caused by the exchange of a neutral serine residue to an arginine residue (positively charged). This exchange is unlikely to have functional consequences as it maps to the C-terminus of the alpha-chain. C3 variants appear to have originated from various independent mutations as we could not detect this mutation in different allotypes.
I Med Klinik and Poliklinik, Johannes Gutenberg University Mainz, Germany.
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Höhler
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Botto
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Rittner
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Schneider
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Meyer zum Büschenfelde
D001483:Base Sequence; D003176:Complement C3 / Q000235:genetics*; D018740:Genetic Heterogeneity; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational
D003176:Complement C3