The complement system and its component C3: candidates for natural resistance to micro-organisms

Since the complement system and its component C3 art candidates for improve d generalised defence power this study was conducted in order to determine the phenotypic variation of complement activity in pigs and to screen for p olymorphism in the porcine C3 gene. Considerable individual variation in to tal haemolytic activity of the classical and alternative complement pathway as well as in C3c serum concentration was found in F2-piglets of a resourc e population. The cDNA sequence of the porcine C3 gene was determined and s creened for polymorphism by DGGE. Six polymorphic sites were detected. One was shown to segregate in the resource family.