Electrophoretic polymorphism and molecular structure of equine C3

Area of Science:

• Immunogenetics
• Equine Genetics
• Complement System Biology

Background:

• The third complement component (C3) plays a crucial role in the innate and adaptive immune response.
• Understanding genetic polymorphism in complement proteins like equine C3 is vital for veterinary immunology and breeding.
• Previous characterization of equine C3 electrophoretic variants was limited.

Purpose of the Study:

• To determine the electrophoretic polymorphism of equine third complement component (C3) in different horse breeds.
• To analyze the submolecular structure of equine C3 variants.
• To investigate the inheritance patterns of equine C3 electrophoretic phenotypes.

Main Methods:

• Plasma and serum samples from Arabian and Standardbred horses were analyzed using immunofixation electrophoresis.
• Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was employed to analyze C3/anti-C3 complexes.
• Family data, including mares, stallions, and offspring, were used for segregation analysis.

Main Results:

• Six distinct electrophoretic patterns (phenotypes) of equine C3 were identified.
• SDS-PAGE revealed that equine C3 consists of alpha and beta chains with consistent molecular weights across variants.
• Family studies indicated that the six phenotypes are controlled by three codominant autosomal alleles (C3-1, C3-2, C3-3).

Conclusions:

• The study successfully characterized six electrophoretic variants of equine C3.
• The molecular structure of equine C3 is conserved among the identified electrophoretic variants.
• Equine C3 exhibits a simple Mendelian inheritance pattern governed by three codominant alleles at a single locus.