, Volume 32, Issue 5, pp 309–312 | Cite as

Molecular characterization of human complement factor B subtypes

  • Christian Davrinche
  • Michel Abbal
  • André Clerc
Original Articles


While several laboratories have agreed that there are two subtypes of the BF*F alleles, no information has been available until now at the molecular level. The region of the BF gene corresponding to the Ba fragment [1.7 kilobases (kb)] of the BF*S, BF*FA, and BF*FB alleles has been sequenced after specific amplification using the polymerase chain reaction (PCR). A point mutation at codon 7 has been revealed converting a cytosine in the BF*S allele to a thymidine in BF*FB. At the translational level an arginine residue in BF*S is substituted for a tryptophan residue in BF*FB. The amino-terminal sequencing of factor B immunoprecipitated from serum has been carried out form microquantities of protein blotted onto polyvinylidene fluoride (PVDF) membranes. We have shown that the difference between the BF*FA and BF*FB subtypes in characterized by a glutamine at position 7 in BF*FA and a tryptophan in BF*FB.


Codon Fluoride Arginine Glutamine Tryptophan 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • Christian Davrinche
    • 1
  • Michel Abbal
    • 1
  • André Clerc
    • 2
  1. 1.INSERMToulouse CedexFrance
  2. 2.CRPG-CNRSToulouse CedexFrance

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