Determining the one, two, three, or four long and short loci of human complement C4 in a major histocompatibility complex haplotype encoding C4A or C4B proteins.

ABSTRACT: The complex genetics of human complement C4 with unusually frequent variations in the size and number of C4A and C4B, as well as their neighboring genes, in the major histocompatibility complex has been a hurdle for accurate epidemiological studies of diseases associated with C4. A comprehensive series of novel or improved techniques has been developed to determine the total gene number of C4 and the relative dosages of C4A and C4B in a diploid genome. These techniques include (1) definitive genomic restriction-fragment-length polymorphisms (RFLPs) based on the discrete duplication patterns of the RCCX (RP-C4-CYP21-TNX) modules and on the specific nucleotide changes for C4A and C4B isotypes; (2) module-specific PCR to give information on the total number of C4 genes by comparing the relati

SUBMITTER: Chung EK 

PROVIDER: S-EPMC378538 | biostudies-literature | 2002 Oct

REPOSITORIES: biostudies-literature