Genetic polymorphism of horse serum protein 3 (SP3).

The research paper discusses findings on the genetic polymorphism of a previously unidentified protein in horse serum, designated as serum protein 3, or SP3.

Overview of Research Methods

• The researchers executed a two-dimensional agarose gel-electrophoresis of horse serum samples. This method involved separating proteins based on how they move in an electric field across a gel.
• The second step of this technique involved a horizontal polyacrylamide gel phase to further separate the proteins.
• A 14% concentration of acrylamide was used in the gel separation process, which allowed the SP3 fractions to be distinctly seen.
• The researchers noticed that the 2-D mobility of SP3 fractions was closely similar to that of albumin, a common protein found in blood plasma.

Finding Four Alleles

• Analysis of the family data revealed that the observed SP3 phenotypes (the physical characteristics resulting from genetics) were controlled by four separate, autosomal, co-dominant alleles: D, F, I, S. Autosomal alleles are those that are present in both sexes and can be inherited from both parents.
• Further evidence indicated that F allele could be sub-divided into two variants: F1 and F2. Although these variants exhibited similarity in mobility, they demonstrated distinct genetic structures.
• Each of these SP3 alleles resulted in one fraction and each of the heterozygous types (possessing two different forms of a particular gene, one inherited from each parent) showed two fractions.

Population Study

• The study extended to the typing of SP3 among over 600 horses representing different horse breeds including the Swedish Trotter, North-Swedish Trotter, Thoroughbred, Arab, and Polish Tarpan.
• The researchers estimated the frequency of the SP3 allele within these populations.
• The findings showed that SP3 was highly polymorphic among all the studied horse breeds. Genetic polymorphism means that different physical forms result from different genetic structures within the same species.

The study concluded with the assertion that the genetic polymorphism of this previously unidentified SP3 protein could play an important role in genetic diversity among horse breeds and potentially influence various aspects of equine health.