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Abstract

Marker-Assisted Selection is getting increasing attention in animal breeding as an effective tool for choosing animals with desirable traits. Identification of molecular markers which are related to candidate genes is a promising approach for improving economic traits and has to be evaluated for further gene-trait associations. Single nucleotide polymorphisms are genetic markers that can be associated with production traits. SNP genotyping has to be done additionally for each breed to see if they are polymorphic and have significant associations with certain traits. Among the candidate genes that influence the expression of productive traits, special attention is drawn to LY49B, EDNRB and CSN3 genes. Gene EDNRB is associated with lethal white foal syndrome, LY49B is responsible for induction of immune response and CSN3 gene is responsible for reproduction traits in horses.
SNPs LY49B с. 1763 C>T, EDNRB g.118 TC/AG and CSN3 g. 66 A>G have been receiving increasing attention as potential markers which are responsible for developing important selection traits in horses. The study was conducted on Ukrainian Riding Horse, Russian Trotter and Orlov Trotter horse breeds (50 animals for each breed). Genotyping was performed using PCR–RFLP method. EDNRB polymorphism g. 118 TC/AG was polymorphic only in the Ukrainian Riding horse breed. This indicates carriers of the lethal mutation of the White Foal Syndrome (LWFS) only in the mentioned breed. SNP CSN3 g. 66 A>G turned out to be polymorphic (with the predominance of A g. 66 allele) and low-informative (i.e., PIC=0,090-0,122) in Ukrainian Riding Horse, Russian Trotter and Orlov Trotterther breeds.  SNP LY49B c. 1763 C> T turned out to be low-polymorphic (with the predominance of G c.1763 allele) but enough informative (i.e., PIC=0,212-0,365) in Ukrainian Riding Horse, Russian Trotter and Orlov Trotterther breeds. Consequently, it is highly prospective to create experimental groups for studied horse breeds to identifying possible associations only for SNP CSN3 g. 66 A>G.

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