In other species: dog , domestic guinea pig

Categories: Immune system phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 613779 (trait) , 120700 (gene)

Links to relevant human diseases in MONDO:

• MONDO:0013417: complement component 3 deficiency

Mendelian trait/disorder: yes

Disease-related: yes

Key variant known: no

Cross-species summary: Complement component 3 consists of two chains, alpha and beta, linked covalently by disulphide bonds. In humans and mice (and therefore presumably in all mammals), the two chains are encoded by a single gene (the C3 gene).

Species-specific symbol: C3D

Species-specific description: C3 deficiency was discovered in a line of rabbits undergoing selection for high and low total complement haemolytic activity (Komatsu, 1985). Preliminary molecular studies by Komatsu (1992) showed that the mutant allele produces only very low levels of C3 mRNA, suggesting a mutation in a control region of the gene. Sequencing is now underway to determine the exact molecular defect.

Clinical features: 10% of normal C3 serum levels; low survival rate; reduced serum bactericidal activity; suppressed delayed-type hypersensitivity

Genetic testing: Using a 1.6 kb fragment of rabbit C2 cDNA as a probe in Southern analysis, the three genotypes at this locus can be detected with either BglII, StuI, or SacI (Komatsu, 1992).