MCT1, MCT4 and CD147 gene polymorphisms in healthy horses and horses with myopathy.

The research investigates the genetic variants (polymorphisms) related to lactate transporter proteins in horses, namely MCT1, MCT4, and CD147, and explores their potential links with exercise-induced muscle disease (myopathy).

Research Focus and Methods

In this study, researchers examined the coding sequence (cDNA) of horse lactate transport proteins — MCT1, MCT4, and CD147 — and looked for polymorphisms, which are genetic variations in DNA. These transport proteins are crucial for lactate transportation in the body, and variations in these genes can affect their function, potentially leading to exercise-induced myopathy.

• The study involved sequencing the cDNA of MCT4 in horses for the first time.
• 16 healthy horses were involved in examining polymorphisms in these protein-encoding genes.
• The researchers also took biopsy samples from 26 horses who showed signs of exercise-induced recurrent myopathy to investigate if there is an association between this condition and genetic variants found in these transporter genes.

Results

The results suggest various polymorphisms existed within the genes encoding these lactate transport proteins.

• Two polymorphisms causing an amino acid sequence change were found in MCT1, where valine (Val) at position 432 changed to isoleucine (Ile), and lysine (Lys) at position 457 altered to glutamine (Gln).
• One polymorphism causing an amino acid sequence change was identified in CD147, where methionine (Met) at position 125 changed to valine (Val).
• However, all the polymorphisms found in MCT4 were silent, meaning they did not affect protein function, and they did not alter the amino acid sequence.

Final Conclusions

The researchers concluded that there is no apparent link between the identified genetic variants of MCT1, MCT4, or CD147 and muscle disease in horses.

• None of the mutations that were discovered in MCT1 or CD147 in equine muscles were associated with myopathy.
• The researchers support the need for future studies aimed at evaluating the physiological role of these polymorphisms, suggesting a functional study design for this purpose.