Disease relevance of C8B

• The absence of these three proteins, DAF(CD55), C8BP and HRF20(CD59), makes cells from the erythropoiesis, thrombopoiesis and myelopoiesis extensively sensitive to complement attack and affected patients suffer from intravascular hemolysis, thrombosis and increased susceptibility to infections [1].

High impact information on C8B

• In blacks, what appears to be a third common allele was found, so that frequencies were 0.692, 0.259, and 0.049 for C8A, C8B, and C8A1 [2].
• C8A and C8B are closely linked on chromosome 1p, whereas C8G is located on chromosome 9q [3].
• Exon-specific polymerase chain reaction (PCR) amplification with primer pairs from the flanking intron sequences was used to amplify all 12 C8B exons separately [3].
• A BamH1 RFLP of the C8B gene [4].
• The beta-chain of human complement component C8 exhibits a structural genetic polymorphism: using isoelectric focusing two major allotypes can be identified (C8B B ('basic') and C8B A ('acidic')) [5].

Biological context of C8B

• Two alleles, C8A and C8B, have been identified in orientals, with gene frequencies of 0.655 and 0.345 [2].
• There was no evidence of allelic association between the C8A and C8B BamHI RFLPs in 62 unrelated haplotypes [6].
• DNA from the family members were studied with regard to a restriction fragment length polymorphism (RFLP) for the C8B gene [7].
• Two population samples comprising 150 Lappish and 1,264 non-Lappish Norwegians were examined for phenotype distributions in C8A and C8B [8].
• Heterozygotes for C8 beta deficiency were identified using a specific PCR assay to detect a C-->T transition in exon 9 of the C8B gene [9].

Associations of C8B with chemical compounds

• Partial sequence analysis after cyanogen bromide cleavage, showed that the sequences of both proteins in the C8-B fraction (C8-B(H) and C8-B(L)) were identical to the 18.5-kDa isoform of MBP [10].

Other interactions of C8B

• These were governed by separate loci designated C8A and C8B for alpha-gamma and beta, respectively [11].

Analytical, diagnostic and therapeutic context of C8B

• In the patient group, one C8B deficient individual was discovered; none in the control group [7].
• The C8-A and C8-B fractions were further purified on HPLC [10].

References