The set according to the invention containing sequence-specific oligonucleotide extension primers for the detection of a total of eight single-nucleotide genetic polymorphisms in the promoter of the MYF5 gene in cattle by a methodology consisting of a two-step polymerase chain reaction (PCR) and subsequent fragmentation analysis of PCR products – amplicons contains 2 primers whose composition is already known from the literature. It also contains 8 SBE extension primers for multiplex detection of genetic polymorphism of the SNP type inside the promoter of the MYF5 gene. This genotyping set of oligonucleotide primers for the determination of mutations in the 5′ untranslated region of the myogenic transcription factor MYF5 gene in cattle enables very accurate and inexpensive determination