title: Direct observation of the gene organization of the complement C4 and 21-hydroxylase loci by pulsed field gel electrophoresis.
abstract: Pulsed field gel electrophoresis and enzymes that cut genomic DNA infrequently have been used to define large RFLPs at the human C4 loci. With the enzymes BssH II or Sac II, and C4 or 21-hydroxylase DNA probes, it has been possible to observe directly the number of C4 genes present on a haplotype, and also whether the C4 genes are long (6-7-kb intron present) or short (6-7-kb intron absent). Haplotypes that have either two long C4 genes or one long and one short C4 gene generate BssH II fragments of approximately 115 or approximately 105 kb, respectively. Haplotypes that have either a single long or a single short C4 gene generate BssH II fragments of approximately 80 or approximately 70 kb, respectively. This technique has been used to analyze the DNA isolated from PBMC and allows the complete definition of the C4 gene organization of an individual without the need for family studies.
authors.affiliation: Department of Biochemistry, University of Oxford, United Kingdom.
authors.forename: I
authors.initials: I
authors.lastname: Dunham
authors.forename: C A
authors.initials: CA
authors.lastname: Sargent
authors.forename: R L
authors.initials: RL
authors.lastname: Dawkins
authors.forename: R D
authors.initials: RD
authors.lastname: Campbell
mesh_terms: D002460:Cell Line; D002874:Chromosome Mapping; D003181:Complement C4 / Q000235:genetics*; D004247:DNA / Q000235:genetics; D015342:DNA Probes; D004262:DNA Restriction Enzymes; D015252:Deoxyribonucleases, Type II Site-Specific; D004586:Electrophoresis; D004587:Electrophoresis, Agar Gel; D006680:HLA Antigens / Q000235:genetics; D006801:Humans; D009693:Nucleic Acid Hybridization; D012150:Polymorphism, Restriction Fragment Length; D013255:Steroid 21-Hydroxylase / Q000235:genetics*; D013250:Steroid Hydroxylases / Q000235:genetics*
chemical_list: D003181:Complement C4; D015342:DNA Probes; D006680:HLA Antigens; D004247:DNA; D013250:Steroid Hydroxylases; D013255:Steroid 21-Hydroxylase; D004262:DNA Restriction Enzymes; C035337:CCGCGG-specific type II deoxyribonucleases; C034510:CTCGAG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific; C027046:TCGA-specific type II deoxyribonucleases